<PAGE>
       As filed with the Securities and Exchange Commission on November 24, 2004
                                                   Registration No. 333-
================================================================================
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  FORM S-8/S-3
                             REGISTRATION STATEMENT
                                      Under
                           The Securities Act of 1933
                                  ----------
                                  GARTNER, INC.
             (Exact name of Registrant as specified in its charter)

         Delaware                                               04-3099750
(State or other jurisdiction of                              (I.R.S. Employer
incorporation or organization)                            Identification Number)

                                 P.O. Box 10212
                               56 Top Gallant Road
                        Stamford, Connecticut 06902-7747
          (Address of principal executive offices, including zip code)
                                  ----------
                  RESTRICTED STOCK AGREEMENT FOR EUGENE A. HALL
                            (Full title of the plan)
                                  ----------
                                Lewis G. Schwartz
                                 General Counsel
                                  Gartner, Inc.
                                 P.O. Box 10212
                               56 Top Gallant Road
                        Stamford, Connecticut 06902-7747
                     (Name and address of agent for service)
                                  ----------
                                 (203) 316-1111
          (Telephone number, including area code, of agent for service)
                                  ----------
                                   Copies to:
                             Larry W. Sonsini, Esq.
                              Robert Sanchez, Esq.
                        Wilson Sonsini Goodrich & Rosati
                            Professional Corporation
                               650 Page Mill Road
                            Palo Alto, CA 94304-1050
                                 (650) 493-9300
                                  ----------
<TABLE>
<CAPTION>
                                                   CALCULATION OF REGISTRATION FEE
====================================================================================================================================
                                                                      Proposed Maximum       Proposed Maximum         Amount of
         Title of Securities to                Amount to be            Offering Price       Aggregate Offering       Registration
             be Registered                    Registered (1)            Per Share (2)            Price (2)             Fee (2)
 --------------------------------------   ------------------------   --------------------   -------------------     ----------------
<S>                                           <C>                     <C>                   <C>                      <C>
 Class A Common Stock
    $0.0005 par value (3)..............         500,000 shares             $11.64               $5,820,000              $737.4
====================================================================================================================================
</TABLE>

(1)  This Registration Statement shall also cover any additional shares of the
     Registrant's Class A Common Stock that become issuable under the Restricted
     Stock Agreement for Eugene A. Hall described herein by reason of any stock
     dividend, stock split, recapitalization or other similar transaction
     effected without the Registrant's receipt of consideration that results in
     an increase in the number of the Registrant's outstanding shares of Class A
     Common Stock.

(2)  Estimated solely for the purpose of calculating the registration fee
     pursuant to Rules 457(c) and (h) under the Securities Act of 1933, as
     amended, on the basis of $11.64 per share, the average of the high and
     low prices per share of the Class A Common Stock on November 23, 2004, as
     reported on the New York Stock Exchange.

(3)  Includes associated rights (the "Rights") to purchase preferred stock.
     Until the occurrence of certain prescribed events, none of which has
     occurred, the Rights are not exercisable.
                                  ----------
================================================================================

<PAGE>

PROSPECTUS

                                 500,000 SHARES

                                  GARTNER, INC.

                              CLASS A COMMON STOCK

                                  ----------

     This Prospectus relates to 500,000 shares of Class A Common Stock (the
"Shares") of Gartner, Inc. (the "Company"), which may be offered from time to
time by the key employee named herein (the "Selling Stockholder") for his own
account. The Company will receive no part of the proceeds from sales made
hereunder. The Shares may be offered by the Selling Stockholder from time to
time in one or more transactions in the over-the-counter market at prices
prevailing therein, in negotiated transactions at such prices as may be agreed
upon, or in a combination of such methods of sale. See "Plan of Distribution."
The price at which any of the Shares may be sold, and the commissions, if any,
paid in connection with any such sale, are unknown and may vary from transaction
to transaction. The Selling Stockholder will bear all sales commissions and
similar expenses. Any other expenses incurred by the Company in connection with
the registration and offering that are not borne by the Selling Stockholder will
be borne by the Company. None of the Shares have been registered prior to the
filing of the Registration Statement of which this Prospectus is a part.

     The Company's Class A Common Stock is traded on The New York Stock Exchange
under the symbol "IT." On November 23, 2004, the last sale price for the
Company's Class A Common Stock as reported on The New York Stock Exchange was
$11.78 per share.

                                  ----------

     THIS OFFERING INVOLVES MATERIAL RISKS. SEE "RISK FACTORS" BEGINNING ON PAGE
3 FOR A DISCUSSION OF FACTORS THAT SHOULD BE CONSIDERED BY PROSPECTIVE
PURCHASERS OF THE SHARES OFFERED BY THIS PROSPECTUS.

                                  ----------

     The Securities and Exchange Commission may take the view that, under
certain circumstances, the Selling Stockholder and any broker-dealers or agents
that participate with the Selling Stockholder in the distribution of the Shares
may be deemed to be underwriters within the meaning of the Securities Act of
1933, as amended. Commissions, discounts or concessions received by any such
broker-dealer or agent may be deemed to be underwriting commissions under the
Securities Act. See "Plan of Distribution."

                                  ----------

     Neither the Securities and Exchange Commission nor any state securities
commission has approved or disapproved of these securities or passed upon the
adequacy or accuracy of this Prospectus. Any representation to the contrary is a
criminal offense.

                                  ----------

                The date of this Prospectus is November 24, 2004

<PAGE>

                                TABLE OF CONTENTS

                                                                            Page
                                                                            ----
GARTNER, INC ...............................................................   1

FORWARD-LOOKING STATEMENTS .................................................   2

RISK FACTORS ...............................................................   3

USE OF PROCEEDS ............................................................   7

SELLING STOCKHOLDER ........................................................   7

PLAN OF DISTRIBUTION .......................................................   7

LEGAL MATTERS ..............................................................   8

EXPERTS ....................................................................   8

INFORMATION INCORPORATED BY REFERENCE ......................................   9

     You should rely only on the information contained or incorporated by
reference in this Prospectus and in any accompanying Prospectus supplement. We
have not authorized anyone to provide you with information different from that
contained in this Prospectus. The shares of Class A Common Stock offered under
this Prospectus are offered only in jurisdictions where offers and sales are
permitted. The information contained in this Prospectus is accurate only as of
the date of this Prospectus, regardless of the time of delivery of this
Prospectus or of any sale of the Class A Common Stock.

     IN THIS PROSPECTUS, THE "COMPANY," "GARTNER," "WE," "US," AND "OUR" REFER
TO GARTNER, INC.

<PAGE>

                                  GARTNER, INC.

     Gartner, Inc., founded in 1979, is a leading independent provider of
research and analysis on information technology, computer hardware, software,
communications and related technology industries (the "IT industry"). We provide
comprehensive coverage of the IT industry to approximately 10,000 client
organizations. We serve a global client base consisting primarily of chief
information officers ("CIOs") and other senior IT and business executives in
corporations and government agencies. We also serve technology companies and the
investment community.

     Our executive offices are located at 56 Top Gallant Road, Stamford,
Connecticut 06902-7747. Our telephone number is (203) 316-1111. Our website is
located on the internet at www.gartner.com.

<PAGE>


                           FORWARD-LOOKING STATEMENTS

     This Prospectus and the documents incorporated into this Prospectus by
reference contain forward-looking statements that we have made pursuant to the
provisions of the Private Securities Litigation Reform Act of 1995. Such
forward-looking statements are not historical facts but rather are based on
current expectations, estimates and projections about our industry, management's
beliefs, and assumptions made by management. Words such as "expects,"
"believes," "seeks," and variations of such words and similar expressions are
intended to identify such forward-looking statements. These statements are not
guarantees of future performance and are subject to certain risks, uncertainties
and other factors, some of which are beyond our control, that are difficult to
predict and could cause actual results to differ materially from those expressed
or forecasted in such forward-looking statements. Such risks and uncertainties
include those described in "Risk Factors" and elsewhere in this Prospectus and
in the documents incorporated into this Prospectus by reference. You are
cautioned not to place undue reliance on these forward-looking statements which
reflect management's view only as of the date of this Prospectus. We undertake
no obligation to update such statements or publicly release the result of any
revisions to these forward-looking statements after the date hereof or to
reflect the occurrence of unanticipated events.


                                       -2-
<PAGE>

                                  RISK FACTORS

     You should carefully consider the risks described below before making a
decision to invest in our Class A Common Stock. The risks described below are
not the only ones facing us. Additional risks not presently known to us or that
we currently deem immaterial may also impair our business operations and
financial situation. Our business, financial condition and results of operations
could be seriously harmed by any of these risks. The trading price of our Class
A Common Stock could decline due to any of these risks, and you may lose all or
part of your investment.

     Economic Conditions. Our revenues and results of operations are influenced
by economic conditions in general and more particularly by business conditions
in the IT industry. A general economic downturn or recession, anywhere in the
world, could negatively affect demand for our products and services and may
substantially reduce existing and potential client information
technology-related budgets. The economic downturn in the United States and
globally has led to constrained IT spending, which has impacted our business and
may materially and adversely affect our business, financial condition and
results of operations, including our ability to: maintain client retention,
wallet retention and consulting utilization rates, and achieve contract value
and consulting backlog. To the extent our clients are in the IT industry, the
severe decline in that sector has also had a significant impact on their
spending.

     Acts of Terrorism or War. Acts of terrorism, acts of war and other
unforeseen events, may cause damage or disruption to our properties, business,
employees, suppliers, distributors and clients, which could have an adverse
effect on our business, financial condition and operating results. Such events
may also result in an economic slowdown in the United States or elsewhere, which
could adversely affect our business, financial condition and operating results.

     Competitive Environment. We face direct competition from a significant
number of independent providers of information products and services, including
information that can be found on the Internet free of charge. We also compete
indirectly against consulting firms and other information providers, including
electronic and print media companies, some of which may have greater financial,
information gathering and marketing resources than we do. These indirect
competitors could choose to compete directly with us in the future. In addition,
limited barriers to entry exist in the markets in which we do business. As a
result, additional new competitors may emerge and existing competitors may start
to provide additional or complementary services. Additionally, technological
advances may provide increased competition from a variety of sources. However,
we believe the breadth and depth of our research assets position us well versus
our competition. Increased competition may result in loss of market share,
diminished value in our products and services, reduced pricing and increased
marketing expenditures. We may not be successful if we cannot compete
effectively on quality of research and analysis, timely delivery of information,
customer service, the ability to offer products to meet changing market needs
for information and analysis, or price.

     Renewal of Research Business by Existing Clients. Some of our success
depends on renewals of our subscription-based research products and services,
which constituted 56% of our revenues for the first nine months of 2004 and 57%
for the nine months of 2003. These research subscription agreements have terms
that generally range from twelve to thirty months. Additionally, as we implement
our strategy to realign our business to client needs, we may shift the type and
pricing of our products which could impact client renewal rates. While client
retention rates were 78% at September 30, 2004 and 76% at September 30, 2003,
there can be no guarantee that we will continue to have this level of client
renewals. Any material decline in renewal rates could have an adverse impact on
our revenues and financial condition.

                                       -3-
<PAGE>


      Non-Recurring Consulting Engagements. Consulting segment revenues
constituted 30% of our revenues for the first nine months of 2004 and 31% for
the first nine months of 2003. These consulting engagements typically are
project-based and non-recurring. Any material decline in our ability to replace
consulting arrangements could have an adverse impact on our revenues and
financial condition.

     Restructuring, Reorganization and Management Team. Our future success
depends, in significant part, upon the continued service and performance of our
senior management and other key personnel. We have recently reorganized our
business around specific client needs. As part of this reorganization, a number
of key management positions have been filled by the promotion of current
employees or the hiring of new employees. Additionally, we have restructured our
workforce in order to streamline operations and strengthen key consulting
practices. If the reorganization and restructuring of our business do not lead
to the results we expect, our ability to effectively deliver our products,
manage our company and carry out our business plan may be impaired. On July 23,
2004, we announced that the Board of Directors named Eugene A. Hall as Chief
Executive Officer. Mr. Hall succeeded Michael Fleisher, who had previously
announced his intention to depart as Gartner's chairman and chief executive
officer. Additionally, James C. Smith, a current Board member, has been named
non-executive chairman of the Board of Directors. Further, on September 28,
2004, we announced that the position of President and Chief Operating Officer,
previously held by Maureen O'Connell, was eliminated and that Mr. Hall would
assume direct responsibility for business operations. If we cannot successfully
integrate our Chief Executive Officer into our senior management team, then our
ability to effectively deliver our products, manage our company and carry out
our business plan may be impaired.

     Hiring and Retention of Employees. Our success depends heavily upon the
quality of our senior management, research analysts, consultants, sales and
other key personnel. We face competition for the limited pool of these qualified
professionals from, among others, technology companies, market research firms,
consulting firms, financial services companies and electronic and print media
companies, some of which have a greater ability to attract and compensate these
professionals. Some of the personnel that we attempt to hire are subject to
non-compete agreements that could impede our short-term recruitment efforts. Any
failure to retain key personnel or hire and train additional qualified personnel
as required to support the evolving needs of our clients or growth in our
business, could adversely affect the quality of our products and services, and
therefore, our future business and operating results.

     Maintenance of Existing Products and Services. We operate in a rapidly
evolving market, and our success depends upon our ability to deliver high
quality and timely research and analysis to our clients. Any failure to continue
to provide credible and reliable information that is useful to our clients could
have a material adverse effect on future business and operating results.
Further, if our predictions prove to be wrong or are not substantiated by
appropriate research, our reputation may suffer and demand for our products and
services may decline. In addition, we must continue to improve our methods for
delivering our products and services in a cost-effective manner. Failure to
increase and improve our electronic delivery capabilities could adversely affect
our future business and operating results.

     Introduction of New Products and Services. The market for our products and
services is characterized by rapidly changing needs for information and
analysis. To maintain our competitive position, we must continue to enhance and
improve our products and services, develop or acquire new products and services
in a timely manner, and appropriately position and price new products and
services relative to the marketplace and our costs of producing them. Any
failure to achieve successful client acceptance of new


                                       -4-
<PAGE>

products and services could have a material adverse effect on our business,
results of operations or financial position.

     International Operations. A substantial portion of our revenues is derived
from sales outside of North America. As a result, our operating results are
subject to the risks inherent in international business activities, including
general political and economic conditions in each country, changes in market
demand as a result of exchange rate fluctuations and tariffs and other trade
barriers, challenges in staffing and managing foreign operations, changes in
regulatory requirements, compliance with numerous foreign laws and regulations,
different or overlapping tax structures, higher levels of United States taxation
on foreign income, and the difficulty of enforcing client agreements, collecting
accounts receivable and protecting intellectual property rights in international
jurisdictions. We rely on local distributors or sales agents in some
international locations. If any of these arrangements are terminated, we may not
be able to replace the arrangement on beneficial terms or on a timely basis.
Additionally, clients of the local distributor or sales agent may not want to
continue to do business with us or our new agent.

     Branding. We believe that our "Gartner" brand is critical to our efforts to
attract and retain clients and that the importance of brand recognition will
increase as competition increases. We may expand our marketing activities to
promote and strengthen the Gartner brand and may need to increase our marketing
budget, hire additional marketing and public relations personnel, expend
additional sums to protect the brand and otherwise increase expenditures to
create and maintain client brand loyalty. If we fail to effectively promote and
maintain the Gartner brand, or incur excessive expenses in doing so, our future
business and operating results could be materially and adversely impacted.

     Indebtedness. We have a $200 million term loan and a $100 million revolving
loan. The affirmative, negative and financial covenants of the loans could limit
our future financial flexibility. The associated debt service costs could impair
future operating results. Our outstanding debt may limit the amount of cash or
additional credit available to us, which could restrain our ability to expand or
enhance products and services, respond to competitive pressures or pursue future
business opportunities requiring substantial investments of additional capital.

     Organizational and Product Integration Related to Acquisitions. We have
made and may continue to make acquisitions of, or significant investments in,
businesses that offer complementary products and services. The risks involved in
each acquisition or investment include the possibility of paying more than the
value we derive from the acquisition, dilution of the interests of our current
stockholders or decreased working capital, increased indebtedness, the
assumption of undisclosed liabilities and unknown and unforeseen risks, the
ability to integrate successfully the operations and personnel of the acquired
business, the ability to retain key personnel of the acquired company, the time
to train the sales force to market and sell the products of the acquired
company, the potential disruption of our ongoing business and the distraction of
management from our business. The realization of any of these risks could
adversely affect our business.

     Enforcement of Our Intellectual Property Rights. We rely on a combination
of copyright, patent, trademark, trade secret, confidentiality, non-compete and
other contractual provisions to protect our intellectual property rights.
Despite our efforts to protect our intellectual property rights, unauthorized
third parties may obtain and use technology or other information that we regard
as proprietary. Our intellectual property rights may not survive a legal
challenge to their validity or provide significant protection for us. The laws
of certain countries do not protect our proprietary rights to the same extent as
the laws of the United States. Accordingly, we may not be able to protect our
intellectual property against unauthorized third-party copying or use, which
could adversely affect our competitive position. Our employees are subject to
non-compete agreements. When the non-competition period expires, former
employees may compete against us. If

                                       -5-
<PAGE>

a former employee chooses to compete against us prior to the expiration of the
non-competition period, there is no assurance that we will be successful in our
efforts to enforce the non-compete provision.

     Possibility of Infringement Claims. Third parties may assert infringement
claims against us. Regardless of the merits, responding to any such claim could
be time consuming, result in costly litigation and require us to enter into
royalty and licensing agreements which may not be offered or available on
reasonable terms. If a successful claim is made against us and we fail to
develop or license a substitute technology at a reasonable cost, our business,
results of operations or financial position could be materially adversely
affected.

     Potential Fluctuations in Operating Results. Our quarterly and annual
operating income may fluctuate in the future as a result of many factors,
including the timing of the execution of research contracts, which typically
occurs in the fourth calendar quarter, the extent of completion of consulting
engagements, the timing of symposia and other events, which also occur to a
greater extent in the fourth calendar quarter, the amount of new business
generated, the mix of domestic and international business, changes in market
demand for our products and services, the timing of the development,
introduction and marketing of new products and services, and competition in the
industry. An inability to generate sufficient earnings and cash flow, and
achieve our forecasts, may impact our operating and other activities. The
potential fluctuations in our operating income could cause period-to-period
comparisons of operating results not to be meaningful and may provide an
unreliable indication of future operating results.

     Significant Stockholder. Silver Lake Partners, L.P. ("SLP") and its
affiliates own approximately 42.8% of our outstanding Class A Common Stock and
approximately 34.0% on a combined basis with our outstanding Class B Common
Stock as of October 31, 2004 Currently, the owners of our Class A Common Stock
are only entitled to vote for two of the ten members of our Board of Directors
and vote together with the holders of the Class B Common Stock as a single class
on all other matters coming before the stockholders. SLP is restricted from
purchasing additional stock without our consent pursuant to the terms of a
Securityholders' Agreement. This Securityholders' Agreement also provides that
we cannot take certain actions, including acquisitions and sales of stock and/or
assets without SLP's consent. While SLP does not hold a majority of our
outstanding shares, it may be able to exercise significant influence over
matters requiring stockholder approval, including the election of directors and
the approval of mergers, consolidations and sales of our assets. SLP's interests
may differ from the interests of other stockholders.

     Anti-takeover Protections. Provisions of our certificate of incorporation
and bylaws and Delaware law may make it difficult for any party to acquire
control of us in a transaction not approved by the requisite number of
directors. These provisions include:

     o    The presence of a classified board of directors;

     o    The existence of two classes of Common Stock with our Class B Common
          Stock having the ability to elect 80% of our Board of Directors;

     o    The ability of the Board of Directors to issue and determine the terms
          of preferred stock;

     o    The existence of a stockholder rights plan;

     o    Advance notice requirements for inclusion of stockholder proposals at
          stockholder meetings; and

     o    The anti-takeover provisions of Delaware law.

                                       -6-
<PAGE>

     These provisions could delay or prevent a change of control or change in
management that might provide stockholders with a premium to the market price of
their Common Stock.

                                 USE OF PROCEEDS

     We will not receive any proceeds from the sale of the Class A Common Stock
by the Selling Stockholder. All net proceeds from the sale of the Class A Common
Stock covered by this Prospectus will go to the Selling Stockholder.

                               SELLING STOCKHOLDER

     The Shares to be offered and sold pursuant to this Prospectus were issued
to the Selling Stockholder in connection with the commencement of his employment
as our Chief Executive Officer. The following table sets forth information with
respect to beneficial ownership of our Class A Common Stock as of October 31,
2004 by the Selling Stockholder.

     The Shares may be offered from time to time by the Selling Stockholder
named below. The Selling Stockholder may offer all, some or none of the Shares
and there currently are no agreements, arrangements or understandings with
respect to the sale of any of the Shares.

                                                                  Number of
                                                                 Shares to be
                         Number of Shares   Number of Shares     Beneficially
                          Owned Prior to     Registered for       Owned After
       Name                  Offering          Sale Hereby         Offering
------------------       ----------------   ----------------     ------------
Eugene A. Hall (1)           500,000 (2)         500,000 (2)          0 (3)

----------
(1)  Eugene A. Hall is our Chief Executive Officer.

(2)  This Prospectus also shall cover any additional shares of Class A Common
     Stock which become issuable in connection with the Shares registered for
     sale hereby by reason of any stock dividend, stock split, recapitalization
     or other similar transaction effected without the receipt of consideration
     which results in an increase in the number of our outstanding shares of
     Class A Common Stock.

(3)  Assumes sale of all of the Shares offered; however, the Selling Stockholder
     may or may not sell any of the offered Shares.


                              PLAN OF DISTRIBUTION

         The Selling Stockholder may, from time to time, sell all or a portion
of the Shares as follows: at prices and at terms then prevailing in the market,
at prices related to the then current market price, or in negotiated
transactions. The Shares may be sold by the Selling Stockholder by one or more
of the following methods, or others:

     o    block trades in which the broker or dealer so engaged will attempt to
          sell the Shares as agent but may position and resell a portion of the
          block as principal to facilitate the transaction,

     o    purchases by a broker or dealer as principal and resale by the broker
          or dealer for its account pursuant to this Prospectus,

     o    on a stock exchange in accordance with the rules of the particular
          exchange, ordinary brokerage transactions and transactions in which
          the broker solicits purchasers,

                                       -7-
<PAGE>

     o    privately negotiated transactions,

     o    or a combination of any of these methods of sale.

     In effecting sales, brokers and dealers engaged by the Selling Stockholder
may arrange for other brokers or dealers to participate. Brokers or dealers may
receive commissions or discounts from the Selling Stockholder, or, if any
broker-dealer acts as agent for the purchaser of the Shares, from the purchaser,
in amounts to be negotiated which are not expected to exceed those customary in
the types of transactions involved. Broker-dealers may agree with the Selling
Stockholder to sell a specified number of the Shares at a stipulated price per
share, and, to the extent the broker-dealer is unable to do so acting as agent
for the Selling Stockholder, to purchase as principal any unsold Shares at the
price required to fulfill the broker-dealer commitment to the Selling
Stockholder. Broker-dealers who acquire Shares as principal may subsequently
resell the Shares from time to time in the following transactions: transactions,
which may involve block transactions and sales to and through other
broker-dealers, in the over-the-counter market or otherwise at prices and on
terms then prevailing at the time of sale, in negotiated transactions, or at
prices related to the then-current market price.

     In connection with these resales, the broker-dealer may pay to or receive
from the purchasers of the Shares commissions as described above.

     The Selling Stockholder and any broker-dealers or agents that participate
with the Selling Stockholder in sales of the Shares may be deemed to be
"underwriters" within the meaning of the Securities Act of 1933, as amended (the
"Securities Act") in connection with any sales. In the event of a sale, any
commissions received by the broker-dealers or agents and any profit on the
resale of the Shares purchased by them may be deemed to be underwriting
commissions or discounts under the Securities Act. In addition, Regulation M
under the Securities Exchange Act of 1934, as amended (the "Exchange Act") may
apply in connection with the Selling Stockholder's sales of his Shares.

     We have agreed to pay all fees and expenses incident to the registration of
the Shares. The Selling Stockholder will pay all commissions and discounts, if
any, attributable to the sales of the Shares. We have agreed to indemnify the
Selling Stockholder against certain losses, claims, damages and liabilities,
including liabilities under the Securities Act.

     The Selling Stockholder may, in the future, also sell the Shares in
accordance with Rule 144 under the Securities Act, rather than pursuant to this
Prospectus.

     There can be no assurance that the Selling Stockholder will sell any or all
of the Shares offered by him hereunder.


                                  LEGAL MATTERS

     The validity of the shares of Class A Common Stock offered by this
Prospectus will be passed upon by Wilson Sonsini Goodrich & Rosati, Professional
Corporation, Palo Alto, California.

                                     EXPERTS


Our consolidated financial statements and schedule supporting such consolidated
financial statements as of December 31, 2003 and 2002, and for the year ended

                                       -8-
<PAGE>

December 31, 2003, the three month period ended December 31, 2002, and each of
the years in the two-year period ended September 30, 2002 included in Gartner,
Inc. and subsidiaries Annual Report on Form 10-K for the year ended December 31,
2003, have been incorporated by reference in this Prospectus in reliance upon
the report of KPMG LLP, independent registered public accounting firm, and upon
the authority of said firm as experts in accounting and auditing. The audit
report dated February 5, 2004 contains an explanatory paragraph indicating that
the Company adopted Statement of Financial Accounting Standards No. 142,
"Goodwill and Other Intangible Assets" in the year ended September 30, 2002.


                      INFORMATION INCORPORATED BY REFERENCE

     The following documents filed with the Securities and Exchange Commission
(the "Commission") are hereby incorporated by reference into this Prospectus:

     o    The Company's Annual Report on Form 10-K for the fiscal year ended
          December 31, 2003, filed with the Commission on March 12, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended
          March 31, 2004, filed with the Commission on May 4, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended June
          30, 2004, filed with the Commission on August 3, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended
          September 30, 2004, filed with the Commission on November 8, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          September 1, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          September 29, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          October 15, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          October 25, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          November 1, 2004;

     o    The Company's Registration Statement on Form 8-A filed with the
          Commission on March 7, 2000, which contains a description of the
          terms, rights and provisions of the Company's Class A Preferred Share
          Purchase Rights attached to and currently trading together with shares
          of the Company's Class A Common Stock, including any amendment or
          report filed for the purpose of updating such description; and

     o    The description of the Company's Class A Common Stock contained in the
          Company's Registration Statement on Form 8-A filed with the Commission
          on July 7, 1999, including any amendment or report filed for the
          purpose of updating such description.

                                       -9-
<PAGE>

     In addition, all documents subsequently filed with the Commission by the
Company pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act on
or after the date of this Registration Statement and prior to the filing of a
post-effective amendment which indicates that all securities offered hereunder
have been sold or which deregisters all securities then remaining unsold under
this Registration Statement (other than Current Reports on Form 8-K containing
Regulation FD disclosure furnished under Item 7.01 or Results of Operations and
Financial Condition disclosure furnished under Item 2.02 and exhibits relating
to such disclosures, unless otherwise specifically stated in such Current Report
on Form 8-K), shall be deemed to be incorporated by reference in this
Registration Statement and to be part hereof from the date of filing of such
documents.

     You may request a copy of these filings, at no cost, by writing or
telephoning our Investor Relations department, at the following address:

                                  Gartner, Inc.
                               56 Top Gallant Road
                               Stamford, CT 06902
                                 (203) 316-1111


     We file annual, quarterly and special reports and other information with
the Commission. You may read and copy any documents we file at the Commission's
Public Reference Room at 450 Fifth Street, N.W., Washington, D.C. 20549. Please
call the Commission at 1-800-SEC-0330 for further information on the public
reference room. Our Commission filings are also available to the public from the
Commission's website at http://www.sec.gov.

     Our Internet address is www.gartner.com and the investor relations section
of our Web site is located at www.gartner.com/investors. We make available free
of charge, on or through the investor relations section of our Web site, annual
reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form
8-K and amendments to those reports filed or furnished pursuant to Section 13(a)
or 15(d) of the Exchange Act as soon as reasonably practicable after we
electronically file such material with, or furnish it to, the Commission.

                                      -10-
<PAGE>

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE

     The following documents and information previously filed with the
Commission by the Company are hereby incorporated in this Registration Statement
by reference:

     o    The Company's Annual Report on Form 10-K for the fiscal year ended
          December 31, 2003, filed with the Commission on March 12, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended
          March 31, 2004, filed with the Commission on May 4, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended June
          30, 2004, filed with the Commission on August 3, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended
          September 30, 2004, filed with the Commission on November 8, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          September 1, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          September 29, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          October 15, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          October 25, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          November 1, 2004;

     o    The Company's Registration Statement on Form 8-A filed with the
          Commission on March 7, 2000, which contains a description of the
          terms, rights and provisions of the Company's Class A Preferred Share
          Purchase Rights attached to and currently trading together with shares
          of the Company's Class A Common Stock, including any amendment or
          report filed for the purpose of updating such description; and

     o    The description of the Company's Class A Common Stock contained in the
          Company's Registration Statement on Form 8-A filed with the Commission
          on July 7, 1999, including any amendment or report filed for the
          purpose of updating such description.

     In addition, all documents subsequently filed with the Commission by the
Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act
on or after the date of this Registration Statement and prior to the filing of a
post-effective amendment which indicates that all securities offered hereunder
have been sold or which deregisters all securities then remaining unsold under
this Registration Statement (other than Current Reports on Form 8-K containing
Regulation FD disclosure furnished under Item 7.01 or Results of Operations and
Financial Condition disclosure furnished under Item 2.02 and exhibits relating
to such

                                      II-1
<PAGE>

disclosures, unless otherwise specifically stated in such Current Report on Form
8-K), shall be deemed to be incorporated by reference in this Registration
Statement and to be part hereof from the date of filing of such documents. Any
statement contained herein or in a document incorporated or deemed to be
incorporated by reference herein shall be deemed to be modified or superseded
for purposes of this Registration Statement to the extent that a statement
contained herein or in any other subsequently filed document which also is or is
deemed to be incorporated by reference herein modifies or supersedes such
earlier statement. Any statement so modified or superseded shall not be deemed,
except as so modified or superseded, to constitute a part of this Registration
Statement.

ITEM 4. DESCRIPTION OF SECURITIES

     Inapplicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL

     The validity of the securities being registered by this Registration
Statement will be passed upon by Wilson Sonsini Goodrich & Rosati, Professional
Corporation, Palo Alto, California.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS

     Section 145 of the Delaware General Corporation Law ("Delaware Law")
provides that a corporation may indemnify a director, officer, employee or agent
made a party to an action by reason of the fact that he was a director, officer,
employee or agent of the corporation, or was serving at the request of the
corporation, against expenses actually and reasonably incurred, including
attorneys' fees, in connection with such action, if he acted in good faith and
in a manner he reasonably believed to be in, or not opposed to, the best
interests of the corporation and, with respect to any criminal action, had no
reasonable cause to believe his conduct was unlawful.

     The Company's Certificate of Incorporation limits, to the maximum extent
permitted by Delaware Law, the personal liability of a director to the
Registrant or its stockholders for monetary damages for breach of fiduciary duty
as a director. The Company's Bylaws provide that the Registrant shall indemnify
its officers and directors to the fullest extent permitted by Delaware Law
against all expense, liability and loss, including attorneys' fees, actually and
reasonably incurred and may purchase and maintain insurance against any
liability asserted and incurred by reason of serving as such, whether or not the
Registrant has the power to indemnify against such liability. The Registrant has
entered into indemnification agreements with its officers and directors
containing provisions which are in some respects broader than the specific
indemnification provisions contained in Delaware Law and which require that, to
the extent the Registrant maintains liability insurance applicable to officers
or directors, each officer and director shall be covered by such policies to the
same extent as are accorded the most favorably insured of the Company's officers
or directors, as the case may be.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED

     The issuance of the shares being offered by the Form S-3 resale Prospectus
were deemed to be exempt from registration under the Securities Act in reliance
upon Section 4(2) of the Securities Act or Regulation D promulgated thereunder.

                                      II-2
<PAGE>

ITEM 8. EXHIBITS

Exhibit
Number                            Description
-------   ----------------------------------------------------------------------
4.1       Amended and Restated Certificate of Incorporation of the Registrant
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2000 as filed on December 29,
          2000).

4.2       Certificate of Amendment of the Restated Certificate of Incorporation
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2001 as filed on December 28,
          2001).

4.3       Certificate of Designation, Preferences and Rights of Series A Junior
          Participating Preferred Stock and Series B Junior Participating
          Preferred Stock of the Registrant (incorporated by reference from the
          Registrant's Form 8-K dated March 1, 2000 as filed on March 7, 2000).

4.4       Amended Bylaws of the Registrant as amended through April 14, 2000
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2000 as filed on December 29,
          2000).

4.5       Form of Certificate for Class A Common Stock, Class A (incorporated by
          reference from the Registrant's Annual Report on Form 10-K for the
          year ended September 30, 2001 as filed on December 28, 2001).

4.6       Amended and Restated Rights Agreement, dated as of August 31, 2002
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2002 as filed on December 27,
          2002).

4.7       Amendment No. 1 to the Amended and Restated Rights Agreement, dated as
          of June 30, 2003 (incorporated by reference from the Registrant's
          Amendment No. 2 to Form 8-A as filed on June 30, 2003).

5.1       Opinion of Wilson Sonsini Goodrich & Rosati, Professional Corporation.

23.1      Consent of Independent Registered Public Accounting Firm.

23.2      Consent of Wilson Sonsini Goodrich & Rosati, Professional Corporation
          (included in Exhibit 5.1 to this Registration Statement).

24.1      Power of Attorney (included in the signature page of this Registration
          Statement).

ITEM 9. UNDERTAKINGS

     (a)  The undersigned Registrant hereby undertakes:

          (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this Registration Statement:

               (i) To include any prospectus required by section 10(a)(3) of the
Securities Act;

               (ii) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent
post-effective amendment thereof) which, individually or in the aggregate,
represent a fundamental change in the information set forth in the registration
statement;

               (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement;


                                      II-3
<PAGE>

     Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if
the information required to be included in a post-effective amendment by those
paragraphs is contained in periodic reports filed by the Registrant pursuant to
section 13 or section 15(d) of the Exchange Act that are incorporated by
reference in the registration statement.

          (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

          (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

     (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to section 13(a) or section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to section 15(d) of the Exchange Act) that is
incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

     (c) Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Act and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by the registrant of expenses incurred
or paid by a director, officer or controlling person of the registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

                                      II-4
<PAGE>

                                   SIGNATURES

THE REGISTRANT

     Pursuant to the requirements of the Securities Act, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8/S-3 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Stamford, state of Connecticut on this 23 day of
November, 2004.

                                               GARTNER, INC.
                                               (Registrant)



                                               By: /s/ Christopher Lafond
                                                   -------------------------
                                                   Christopher Lafond
                                                   Executive Vice President,
                                                   Chief Financial Officer

                                POWER OF ATTORNEY

     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Eugene A. Hall and Christopher Lafond,
and each of them, his true and lawful attorneys-in-fact, each with the power of
substitution, for him and his name, place and stead, in any and all capacities,
to sign any and all amendments (including post-effective amendments) to this
Registration Statement, and to sign any registration statement for the same
offering covered by this Registration Statement that are to be effective upon
filing pursuant to Rule 462(b) promulgated under the Securities Act, as amended,
and all post-effective amendments thereto, and to file the same, with all
exhibits thereto in all documents in connection therewith, with the Commission,
granting unto said attorneys-in-fact and agents, and each of them, full power
and authority to do and perform each and every act and thing requisite and
necessary to be done in and about the premises, as fully to all intents and
purposes as he might or could do in person, hereby ratifying and confirming all
that such attorneys-in-fact and agents or any of them, or his or their
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     Pursuant to the requirements of the Securities Act, this Registration
Statement has been signed by the following persons in the capacities and on the
dates indicated.

<TABLE>
<CAPTION>
                Signature                                        Title                              Date
--------------------------------------     -----------------------------------------------    -----------------
<S>                                        <C>                                                <C>
/s/ Eugene A. Hall                         Director and Chief Executive Officer (Principal    November 23, 2004
--------------------------------------     Executive Officer)
Eugene A. Hall

/s/ Christopher Lafond                     Executive Vice President, Chief Financial          November 23, 2004
--------------------------------------     Officer (Principal Financial and Accounting
Christopher Lafond                         Officer)
</TABLE>


                                      II-5
<PAGE>

<TABLE>
<CAPTION>
                Signature                                        Title                              Date
--------------------------------------     -----------------------------------------------    -----------------
<S>                                        <C>                                                <C>
/s/ Anne Sutherland Fuchs                  Director                                           November 23, 2004
--------------------------------------
Anne Sutherland Fuchs

/s/ William O. Grabe                       Director                                           November 23, 2004
--------------------------------------
William O. Grabe

/s/ Max D. Hopper                          Director                                           November 23, 2004
--------------------------------------
Max D. Hopper

/s/ Glenn H. Hutchins                      Director                                           November 23, 2004
--------------------------------------
Glenn H. Hutchins

/s/ Stephen G. Pagliuca                    Director                                           November 23, 2004
--------------------------------------
Stephen G. Pagliuca

/s/ James C. Smith                         Chairman of the Board                              November 23, 2004
--------------------------------------
James C. Smith

/s/ Michael J. Bingle                      Director                                           November 23, 2004
--------------------------------------
Michael J. Bingle

/s/ Jeffrey W. Ubben                       Director                                           November 23, 2004
--------------------------------------
Jeffrey W. Ubben

/s/ Maynard G. Webb, Jr.                   Director                                           November 23, 2004
--------------------------------------
Maynard G. Webb, Jr.
</TABLE>

                                      II-6
<PAGE>

                                  EXHIBIT INDEX

Exhibit
Number                            Description
-------   ----------------------------------------------------------------------
4.1       Amended and Restated Certificate of Incorporation of the Registrant
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2000 as filed on December 29,
          2000).

4.2       Certificate of Amendment of the Restated Certificate of Incorporation
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2001 as filed on December 28,
          2001).

4.3       Certificate of Designation, Preferences and Rights of Series A Junior
          Participating Preferred Stock and Series B Junior Participating
          Preferred Stock of the Registrant (incorporated by reference from the
          Registrant's Form 8-K dated March 1, 2000 as filed on March 7, 2000).

4.4       Amended Bylaws of the Registrant as amended through April 14, 2000
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2000 as filed on December 29,
          2000).

4.5       Form of Certificate for Class A Common Stock, Class A (incorporated by
          reference from the Registrant's Annual Report on Form 10-K for the
          year ended September 30, 2001 as filed on December 28, 2001).

4.6       Amended and Restated Rights Agreement, dated as of August 31, 2002
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2002 as filed on December 27,
          2002).

4.7       Amendment No. 1 to the Amended and Restated Rights Agreement, dated as
          of June 30, 2003 (incorporated by reference from the Registrant's
          Amendment No. 2 to Form 8-A as filed on June 30, 2003).

5.1       Opinion of Wilson Sonsini Goodrich & Rosati, Professional Corporation.

23.1      Consent of Independent Registered Public Accounting Firm.

23.2      Consent of Wilson Sonsini Goodrich & Rosati, Professional Corporation
          (included in Exhibit 5.1 to this Registration Statement).

24.1      Power of Attorney (included in the signature page of this Registration
          Statement).


                                      II-7
[{"type": "S-8", "sequence": "1", "filename": "y69125sv8.txt", "description": "ORIGINAL FILING ON FORM S-8: GARTNER, INC.", "secsgml_size_bytes": 59988}]
{"company-data": {"conformed-name": "GARTNER INC", "cik": "0000749251", "assigned-sic": "8741", "irs-number": "043099750", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-120767", "film-number": "041167518"}, "business-address": {"street1": "56 TOP GALLANT RD", "street2": "P O BOX 10212", "city": "STAMFORD", "state": "CT", "zip": "06904-2212", "phone": "2039640096"}, "mail-address": {"street1": "56 TOP GALLANT RD", "street2": "P O BOX 10212", "city": "STAMFORD", "state": "CT", "zip": "06904-2212"}, "former-company": {"former-conformed-name": "GARTNER GROUP INC", "date-changed": "19930823"}}
As filed with the Securities and Exchange Commission on November 24, 2004
                                                   Registration No. 333-
================================================================================
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                  FORM S-8/S-3
                             REGISTRATION STATEMENT
                                      Under
                           The Securities Act of 1933
                                  ----------
                                  GARTNER, INC.
             (Exact name of Registrant as specified in its charter)

         Delaware                                               04-3099750
(State or other jurisdiction of                              (I.R.S. Employer
incorporation or organization)                            Identification Number)

                                 P.O. Box 10212
                               56 Top Gallant Road
                        Stamford, Connecticut 06902-7747
          (Address of principal executive offices, including zip code)
                                  ----------
                  RESTRICTED STOCK AGREEMENT FOR EUGENE A. HALL
                            (Full title of the plan)
                                  ----------
                                Lewis G. Schwartz
                                 General Counsel
                                  Gartner, Inc.
                                 P.O. Box 10212
                               56 Top Gallant Road
                        Stamford, Connecticut 06902-7747
                     (Name and address of agent for service)
                                  ----------
                                 (203) 316-1111
          (Telephone number, including area code, of agent for service)
                                  ----------
                                   Copies to:
                             Larry W. Sonsini, Esq.
                              Robert Sanchez, Esq.
                        Wilson Sonsini Goodrich & Rosati
                            Professional Corporation
                               650 Page Mill Road
                            Palo Alto, CA 94304-1050
                                 (650) 493-9300
                                  ----------
CALCULATION OF REGISTRATION FEE
====================================================================================================================================
                                                                      Proposed Maximum       Proposed Maximum         Amount of
         Title of Securities to                Amount to be            Offering Price       Aggregate Offering       Registration
             be Registered                    Registered (1)            Per Share (2)            Price (2)             Fee (2)
 --------------------------------------   ------------------------   --------------------   -------------------     ----------------
Class A Common Stock
    $0.0005 par value (3)..............         500,000 shares             $11.64               $5,820,000              $737.4
====================================================================================================================================
(1)  This Registration Statement shall also cover any additional shares of the
     Registrant's Class A Common Stock that become issuable under the Restricted
     Stock Agreement for Eugene A. Hall described herein by reason of any stock
     dividend, stock split, recapitalization or other similar transaction
     effected without the Registrant's receipt of consideration that results in
     an increase in the number of the Registrant's outstanding shares of Class A
     Common Stock.

(2)  Estimated solely for the purpose of calculating the registration fee
     pursuant to Rules 457(c) and (h) under the Securities Act of 1933, as
     amended, on the basis of $11.64 per share, the average of the high and
     low prices per share of the Class A Common Stock on November 23, 2004, as
     reported on the New York Stock Exchange.

(3)  Includes associated rights (the "Rights") to purchase preferred stock.
     Until the occurrence of certain prescribed events, none of which has
     occurred, the Rights are not exercisable.
                                  ----------
================================================================================
PROSPECTUS

                                 500,000 SHARES

                                  GARTNER, INC.

                              CLASS A COMMON STOCK

                                  ----------

     This Prospectus relates to 500,000 shares of Class A Common Stock (the
"Shares") of Gartner, Inc. (the "Company"), which may be offered from time to
time by the key employee named herein (the "Selling Stockholder") for his own
account. The Company will receive no part of the proceeds from sales made
hereunder. The Shares may be offered by the Selling Stockholder from time to
time in one or more transactions in the over-the-counter market at prices
prevailing therein, in negotiated transactions at such prices as may be agreed
upon, or in a combination of such methods of sale. See "Plan of Distribution."
The price at which any of the Shares may be sold, and the commissions, if any,
paid in connection with any such sale, are unknown and may vary from transaction
to transaction. The Selling Stockholder will bear all sales commissions and
similar expenses. Any other expenses incurred by the Company in connection with
the registration and offering that are not borne by the Selling Stockholder will
be borne by the Company. None of the Shares have been registered prior to the
filing of the Registration Statement of which this Prospectus is a part.

     The Company's Class A Common Stock is traded on The New York Stock Exchange
under the symbol "IT." On November 23, 2004, the last sale price for the
Company's Class A Common Stock as reported on The New York Stock Exchange was
$11.78 per share.

                                  ----------

     THIS OFFERING INVOLVES MATERIAL RISKS. SEE "RISK FACTORS" BEGINNING ON PAGE
3 FOR A DISCUSSION OF FACTORS THAT SHOULD BE CONSIDERED BY PROSPECTIVE
PURCHASERS OF THE SHARES OFFERED BY THIS PROSPECTUS.

                                  ----------

     The Securities and Exchange Commission may take the view that, under
certain circumstances, the Selling Stockholder and any broker-dealers or agents
that participate with the Selling Stockholder in the distribution of the Shares
may be deemed to be underwriters within the meaning of the Securities Act of
1933, as amended. Commissions, discounts or concessions received by any such
broker-dealer or agent may be deemed to be underwriting commissions under the
Securities Act. See "Plan of Distribution."

                                  ----------

     Neither the Securities and Exchange Commission nor any state securities
commission has approved or disapproved of these securities or passed upon the
adequacy or accuracy of this Prospectus. Any representation to the contrary is a
criminal offense.

                                  ----------

                The date of this Prospectus is November 24, 2004
TABLE OF CONTENTS

                                                                            Page
                                                                            ----
GARTNER, INC ...............................................................   1

FORWARD-LOOKING STATEMENTS .................................................   2

RISK FACTORS ...............................................................   3

USE OF PROCEEDS ............................................................   7

SELLING STOCKHOLDER ........................................................   7

PLAN OF DISTRIBUTION .......................................................   7

LEGAL MATTERS ..............................................................   8

EXPERTS ....................................................................   8

INFORMATION INCORPORATED BY REFERENCE ......................................   9

     You should rely only on the information contained or incorporated by
reference in this Prospectus and in any accompanying Prospectus supplement. We
have not authorized anyone to provide you with information different from that
contained in this Prospectus. The shares of Class A Common Stock offered under
this Prospectus are offered only in jurisdictions where offers and sales are
permitted. The information contained in this Prospectus is accurate only as of
the date of this Prospectus, regardless of the time of delivery of this
Prospectus or of any sale of the Class A Common Stock.

     IN THIS PROSPECTUS, THE "COMPANY," "GARTNER," "WE," "US," AND "OUR" REFER
TO GARTNER, INC.
GARTNER, INC.

     Gartner, Inc., founded in 1979, is a leading independent provider of
research and analysis on information technology, computer hardware, software,
communications and related technology industries (the "IT industry"). We provide
comprehensive coverage of the IT industry to approximately 10,000 client
organizations. We serve a global client base consisting primarily of chief
information officers ("CIOs") and other senior IT and business executives in
corporations and government agencies. We also serve technology companies and the
investment community.

     Our executive offices are located at 56 Top Gallant Road, Stamford,
Connecticut 06902-7747. Our telephone number is (203) 316-1111. Our website is
located on the internet at www.gartner.com.
FORWARD-LOOKING STATEMENTS

     This Prospectus and the documents incorporated into this Prospectus by
reference contain forward-looking statements that we have made pursuant to the
provisions of the Private Securities Litigation Reform Act of 1995. Such
forward-looking statements are not historical facts but rather are based on
current expectations, estimates and projections about our industry, management's
beliefs, and assumptions made by management. Words such as "expects,"
"believes," "seeks," and variations of such words and similar expressions are
intended to identify such forward-looking statements. These statements are not
guarantees of future performance and are subject to certain risks, uncertainties
and other factors, some of which are beyond our control, that are difficult to
predict and could cause actual results to differ materially from those expressed
or forecasted in such forward-looking statements. Such risks and uncertainties
include those described in "Risk Factors" and elsewhere in this Prospectus and
in the documents incorporated into this Prospectus by reference. You are
cautioned not to place undue reliance on these forward-looking statements which
reflect management's view only as of the date of this Prospectus. We undertake
no obligation to update such statements or publicly release the result of any
revisions to these forward-looking statements after the date hereof or to
reflect the occurrence of unanticipated events.

                                       -2-
RISK FACTORS

     You should carefully consider the risks described below before making a
decision to invest in our Class A Common Stock. The risks described below are
not the only ones facing us. Additional risks not presently known to us or that
we currently deem immaterial may also impair our business operations and
financial situation. Our business, financial condition and results of operations
could be seriously harmed by any of these risks. The trading price of our Class
A Common Stock could decline due to any of these risks, and you may lose all or
part of your investment.

     Economic Conditions. Our revenues and results of operations are influenced
by economic conditions in general and more particularly by business conditions
in the IT industry. A general economic downturn or recession, anywhere in the
world, could negatively affect demand for our products and services and may
substantially reduce existing and potential client information
technology-related budgets. The economic downturn in the United States and
globally has led to constrained IT spending, which has impacted our business and
may materially and adversely affect our business, financial condition and
results of operations, including our ability to: maintain client retention,
wallet retention and consulting utilization rates, and achieve contract value
and consulting backlog. To the extent our clients are in the IT industry, the
severe decline in that sector has also had a significant impact on their
spending.

     Acts of Terrorism or War. Acts of terrorism, acts of war and other
unforeseen events, may cause damage or disruption to our properties, business,
employees, suppliers, distributors and clients, which could have an adverse
effect on our business, financial condition and operating results. Such events
may also result in an economic slowdown in the United States or elsewhere, which
could adversely affect our business, financial condition and operating results.

     Competitive Environment. We face direct competition from a significant
number of independent providers of information products and services, including
information that can be found on the Internet free of charge. We also compete
indirectly against consulting firms and other information providers, including
electronic and print media companies, some of which may have greater financial,
information gathering and marketing resources than we do. These indirect
competitors could choose to compete directly with us in the future. In addition,
limited barriers to entry exist in the markets in which we do business. As a
result, additional new competitors may emerge and existing competitors may start
to provide additional or complementary services. Additionally, technological
advances may provide increased competition from a variety of sources. However,
we believe the breadth and depth of our research assets position us well versus
our competition. Increased competition may result in loss of market share,
diminished value in our products and services, reduced pricing and increased
marketing expenditures. We may not be successful if we cannot compete
effectively on quality of research and analysis, timely delivery of information,
customer service, the ability to offer products to meet changing market needs
for information and analysis, or price.

     Renewal of Research Business by Existing Clients. Some of our success
depends on renewals of our subscription-based research products and services,
which constituted 56% of our revenues for the first nine months of 2004 and 57%
for the nine months of 2003. These research subscription agreements have terms
that generally range from twelve to thirty months. Additionally, as we implement
our strategy to realign our business to client needs, we may shift the type and
pricing of our products which could impact client renewal rates. While client
retention rates were 78% at September 30, 2004 and 76% at September 30, 2003,
there can be no guarantee that we will continue to have this level of client
renewals. Any material decline in renewal rates could have an adverse impact on
our revenues and financial condition.

                                       -3-
Non-Recurring Consulting Engagements. Consulting segment revenues
constituted 30% of our revenues for the first nine months of 2004 and 31% for
the first nine months of 2003. These consulting engagements typically are
project-based and non-recurring. Any material decline in our ability to replace
consulting arrangements could have an adverse impact on our revenues and
financial condition.

     Restructuring, Reorganization and Management Team. Our future success
depends, in significant part, upon the continued service and performance of our
senior management and other key personnel. We have recently reorganized our
business around specific client needs. As part of this reorganization, a number
of key management positions have been filled by the promotion of current
employees or the hiring of new employees. Additionally, we have restructured our
workforce in order to streamline operations and strengthen key consulting
practices. If the reorganization and restructuring of our business do not lead
to the results we expect, our ability to effectively deliver our products,
manage our company and carry out our business plan may be impaired. On July 23,
2004, we announced that the Board of Directors named Eugene A. Hall as Chief
Executive Officer. Mr. Hall succeeded Michael Fleisher, who had previously
announced his intention to depart as Gartner's chairman and chief executive
officer. Additionally, James C. Smith, a current Board member, has been named
non-executive chairman of the Board of Directors. Further, on September 28,
2004, we announced that the position of President and Chief Operating Officer,
previously held by Maureen O'Connell, was eliminated and that Mr. Hall would
assume direct responsibility for business operations. If we cannot successfully
integrate our Chief Executive Officer into our senior management team, then our
ability to effectively deliver our products, manage our company and carry out
our business plan may be impaired.

     Hiring and Retention of Employees. Our success depends heavily upon the
quality of our senior management, research analysts, consultants, sales and
other key personnel. We face competition for the limited pool of these qualified
professionals from, among others, technology companies, market research firms,
consulting firms, financial services companies and electronic and print media
companies, some of which have a greater ability to attract and compensate these
professionals. Some of the personnel that we attempt to hire are subject to
non-compete agreements that could impede our short-term recruitment efforts. Any
failure to retain key personnel or hire and train additional qualified personnel
as required to support the evolving needs of our clients or growth in our
business, could adversely affect the quality of our products and services, and
therefore, our future business and operating results.

     Maintenance of Existing Products and Services. We operate in a rapidly
evolving market, and our success depends upon our ability to deliver high
quality and timely research and analysis to our clients. Any failure to continue
to provide credible and reliable information that is useful to our clients could
have a material adverse effect on future business and operating results.
Further, if our predictions prove to be wrong or are not substantiated by
appropriate research, our reputation may suffer and demand for our products and
services may decline. In addition, we must continue to improve our methods for
delivering our products and services in a cost-effective manner. Failure to
increase and improve our electronic delivery capabilities could adversely affect
our future business and operating results.

     Introduction of New Products and Services. The market for our products and
services is characterized by rapidly changing needs for information and
analysis. To maintain our competitive position, we must continue to enhance and
improve our products and services, develop or acquire new products and services
in a timely manner, and appropriately position and price new products and
services relative to the marketplace and our costs of producing them. Any
failure to achieve successful client acceptance of new

                                       -4-
products and services could have a material adverse effect on our business,
results of operations or financial position.

     International Operations. A substantial portion of our revenues is derived
from sales outside of North America. As a result, our operating results are
subject to the risks inherent in international business activities, including
general political and economic conditions in each country, changes in market
demand as a result of exchange rate fluctuations and tariffs and other trade
barriers, challenges in staffing and managing foreign operations, changes in
regulatory requirements, compliance with numerous foreign laws and regulations,
different or overlapping tax structures, higher levels of United States taxation
on foreign income, and the difficulty of enforcing client agreements, collecting
accounts receivable and protecting intellectual property rights in international
jurisdictions. We rely on local distributors or sales agents in some
international locations. If any of these arrangements are terminated, we may not
be able to replace the arrangement on beneficial terms or on a timely basis.
Additionally, clients of the local distributor or sales agent may not want to
continue to do business with us or our new agent.

     Branding. We believe that our "Gartner" brand is critical to our efforts to
attract and retain clients and that the importance of brand recognition will
increase as competition increases. We may expand our marketing activities to
promote and strengthen the Gartner brand and may need to increase our marketing
budget, hire additional marketing and public relations personnel, expend
additional sums to protect the brand and otherwise increase expenditures to
create and maintain client brand loyalty. If we fail to effectively promote and
maintain the Gartner brand, or incur excessive expenses in doing so, our future
business and operating results could be materially and adversely impacted.

     Indebtedness. We have a $200 million term loan and a $100 million revolving
loan. The affirmative, negative and financial covenants of the loans could limit
our future financial flexibility. The associated debt service costs could impair
future operating results. Our outstanding debt may limit the amount of cash or
additional credit available to us, which could restrain our ability to expand or
enhance products and services, respond to competitive pressures or pursue future
business opportunities requiring substantial investments of additional capital.

     Organizational and Product Integration Related to Acquisitions. We have
made and may continue to make acquisitions of, or significant investments in,
businesses that offer complementary products and services. The risks involved in
each acquisition or investment include the possibility of paying more than the
value we derive from the acquisition, dilution of the interests of our current
stockholders or decreased working capital, increased indebtedness, the
assumption of undisclosed liabilities and unknown and unforeseen risks, the
ability to integrate successfully the operations and personnel of the acquired
business, the ability to retain key personnel of the acquired company, the time
to train the sales force to market and sell the products of the acquired
company, the potential disruption of our ongoing business and the distraction of
management from our business. The realization of any of these risks could
adversely affect our business.

     Enforcement of Our Intellectual Property Rights. We rely on a combination
of copyright, patent, trademark, trade secret, confidentiality, non-compete and
other contractual provisions to protect our intellectual property rights.
Despite our efforts to protect our intellectual property rights, unauthorized
third parties may obtain and use technology or other information that we regard
as proprietary. Our intellectual property rights may not survive a legal
challenge to their validity or provide significant protection for us. The laws
of certain countries do not protect our proprietary rights to the same extent as
the laws of the United States. Accordingly, we may not be able to protect our
intellectual property against unauthorized third-party copying or use, which
could adversely affect our competitive position. Our employees are subject to
non-compete agreements. When the non-competition period expires, former
employees may compete against us. If

                                       -5-
a former employee chooses to compete against us prior to the expiration of the
non-competition period, there is no assurance that we will be successful in our
efforts to enforce the non-compete provision.

     Possibility of Infringement Claims. Third parties may assert infringement
claims against us. Regardless of the merits, responding to any such claim could
be time consuming, result in costly litigation and require us to enter into
royalty and licensing agreements which may not be offered or available on
reasonable terms. If a successful claim is made against us and we fail to
develop or license a substitute technology at a reasonable cost, our business,
results of operations or financial position could be materially adversely
affected.

     Potential Fluctuations in Operating Results. Our quarterly and annual
operating income may fluctuate in the future as a result of many factors,
including the timing of the execution of research contracts, which typically
occurs in the fourth calendar quarter, the extent of completion of consulting
engagements, the timing of symposia and other events, which also occur to a
greater extent in the fourth calendar quarter, the amount of new business
generated, the mix of domestic and international business, changes in market
demand for our products and services, the timing of the development,
introduction and marketing of new products and services, and competition in the
industry. An inability to generate sufficient earnings and cash flow, and
achieve our forecasts, may impact our operating and other activities. The
potential fluctuations in our operating income could cause period-to-period
comparisons of operating results not to be meaningful and may provide an
unreliable indication of future operating results.

     Significant Stockholder. Silver Lake Partners, L.P. ("SLP") and its
affiliates own approximately 42.8% of our outstanding Class A Common Stock and
approximately 34.0% on a combined basis with our outstanding Class B Common
Stock as of October 31, 2004 Currently, the owners of our Class A Common Stock
are only entitled to vote for two of the ten members of our Board of Directors
and vote together with the holders of the Class B Common Stock as a single class
on all other matters coming before the stockholders. SLP is restricted from
purchasing additional stock without our consent pursuant to the terms of a
Securityholders' Agreement. This Securityholders' Agreement also provides that
we cannot take certain actions, including acquisitions and sales of stock and/or
assets without SLP's consent. While SLP does not hold a majority of our
outstanding shares, it may be able to exercise significant influence over
matters requiring stockholder approval, including the election of directors and
the approval of mergers, consolidations and sales of our assets. SLP's interests
may differ from the interests of other stockholders.

     Anti-takeover Protections. Provisions of our certificate of incorporation
and bylaws and Delaware law may make it difficult for any party to acquire
control of us in a transaction not approved by the requisite number of
directors. These provisions include:

     o    The presence of a classified board of directors;

     o    The existence of two classes of Common Stock with our Class B Common
          Stock having the ability to elect 80% of our Board of Directors;

     o    The ability of the Board of Directors to issue and determine the terms
          of preferred stock;

     o    The existence of a stockholder rights plan;

     o    Advance notice requirements for inclusion of stockholder proposals at
          stockholder meetings; and

     o    The anti-takeover provisions of Delaware law.

                                       -6-
These provisions could delay or prevent a change of control or change in
management that might provide stockholders with a premium to the market price of
their Common Stock.

                                 USE OF PROCEEDS

     We will not receive any proceeds from the sale of the Class A Common Stock
by the Selling Stockholder. All net proceeds from the sale of the Class A Common
Stock covered by this Prospectus will go to the Selling Stockholder.

                               SELLING STOCKHOLDER

     The Shares to be offered and sold pursuant to this Prospectus were issued
to the Selling Stockholder in connection with the commencement of his employment
as our Chief Executive Officer. The following table sets forth information with
respect to beneficial ownership of our Class A Common Stock as of October 31,
2004 by the Selling Stockholder.

     The Shares may be offered from time to time by the Selling Stockholder
named below. The Selling Stockholder may offer all, some or none of the Shares
and there currently are no agreements, arrangements or understandings with
respect to the sale of any of the Shares.

                                                                  Number of
                                                                 Shares to be
                         Number of Shares   Number of Shares     Beneficially
                          Owned Prior to     Registered for       Owned After
       Name                  Offering          Sale Hereby         Offering
------------------       ----------------   ----------------     ------------
Eugene A. Hall (1)           500,000 (2)         500,000 (2)          0 (3)

----------
(1)  Eugene A. Hall is our Chief Executive Officer.

(2)  This Prospectus also shall cover any additional shares of Class A Common
     Stock which become issuable in connection with the Shares registered for
     sale hereby by reason of any stock dividend, stock split, recapitalization
     or other similar transaction effected without the receipt of consideration
     which results in an increase in the number of our outstanding shares of
     Class A Common Stock.

(3)  Assumes sale of all of the Shares offered; however, the Selling Stockholder
     may or may not sell any of the offered Shares.

                              PLAN OF DISTRIBUTION

         The Selling Stockholder may, from time to time, sell all or a portion
of the Shares as follows: at prices and at terms then prevailing in the market,
at prices related to the then current market price, or in negotiated
transactions. The Shares may be sold by the Selling Stockholder by one or more
of the following methods, or others:

     o    block trades in which the broker or dealer so engaged will attempt to
          sell the Shares as agent but may position and resell a portion of the
          block as principal to facilitate the transaction,

     o    purchases by a broker or dealer as principal and resale by the broker
          or dealer for its account pursuant to this Prospectus,

     o    on a stock exchange in accordance with the rules of the particular
          exchange, ordinary brokerage transactions and transactions in which
          the broker solicits purchasers,

                                       -7-
o    privately negotiated transactions,

     o    or a combination of any of these methods of sale.

     In effecting sales, brokers and dealers engaged by the Selling Stockholder
may arrange for other brokers or dealers to participate. Brokers or dealers may
receive commissions or discounts from the Selling Stockholder, or, if any
broker-dealer acts as agent for the purchaser of the Shares, from the purchaser,
in amounts to be negotiated which are not expected to exceed those customary in
the types of transactions involved. Broker-dealers may agree with the Selling
Stockholder to sell a specified number of the Shares at a stipulated price per
share, and, to the extent the broker-dealer is unable to do so acting as agent
for the Selling Stockholder, to purchase as principal any unsold Shares at the
price required to fulfill the broker-dealer commitment to the Selling
Stockholder. Broker-dealers who acquire Shares as principal may subsequently
resell the Shares from time to time in the following transactions: transactions,
which may involve block transactions and sales to and through other
broker-dealers, in the over-the-counter market or otherwise at prices and on
terms then prevailing at the time of sale, in negotiated transactions, or at
prices related to the then-current market price.

     In connection with these resales, the broker-dealer may pay to or receive
from the purchasers of the Shares commissions as described above.

     The Selling Stockholder and any broker-dealers or agents that participate
with the Selling Stockholder in sales of the Shares may be deemed to be
"underwriters" within the meaning of the Securities Act of 1933, as amended (the
"Securities Act") in connection with any sales. In the event of a sale, any
commissions received by the broker-dealers or agents and any profit on the
resale of the Shares purchased by them may be deemed to be underwriting
commissions or discounts under the Securities Act. In addition, Regulation M
under the Securities Exchange Act of 1934, as amended (the "Exchange Act") may
apply in connection with the Selling Stockholder's sales of his Shares.

     We have agreed to pay all fees and expenses incident to the registration of
the Shares. The Selling Stockholder will pay all commissions and discounts, if
any, attributable to the sales of the Shares. We have agreed to indemnify the
Selling Stockholder against certain losses, claims, damages and liabilities,
including liabilities under the Securities Act.

     The Selling Stockholder may, in the future, also sell the Shares in
accordance with Rule 144 under the Securities Act, rather than pursuant to this
Prospectus.

     There can be no assurance that the Selling Stockholder will sell any or all
of the Shares offered by him hereunder.

                                  LEGAL MATTERS

     The validity of the shares of Class A Common Stock offered by this
Prospectus will be passed upon by Wilson Sonsini Goodrich & Rosati, Professional
Corporation, Palo Alto, California.

                                     EXPERTS

Our consolidated financial statements and schedule supporting such consolidated
financial statements as of December 31, 2003 and 2002, and for the year ended

                                       -8-
December 31, 2003, the three month period ended December 31, 2002, and each of
the years in the two-year period ended September 30, 2002 included in Gartner,
Inc. and subsidiaries Annual Report on Form 10-K for the year ended December 31,
2003, have been incorporated by reference in this Prospectus in reliance upon
the report of KPMG LLP, independent registered public accounting firm, and upon
the authority of said firm as experts in accounting and auditing. The audit
report dated February 5, 2004 contains an explanatory paragraph indicating that
the Company adopted Statement of Financial Accounting Standards No. 142,
"Goodwill and Other Intangible Assets" in the year ended September 30, 2002.

                      INFORMATION INCORPORATED BY REFERENCE

     The following documents filed with the Securities and Exchange Commission
(the "Commission") are hereby incorporated by reference into this Prospectus:

     o    The Company's Annual Report on Form 10-K for the fiscal year ended
          December 31, 2003, filed with the Commission on March 12, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended
          March 31, 2004, filed with the Commission on May 4, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended June
          30, 2004, filed with the Commission on August 3, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended
          September 30, 2004, filed with the Commission on November 8, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          September 1, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          September 29, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          October 15, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          October 25, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          November 1, 2004;

     o    The Company's Registration Statement on Form 8-A filed with the
          Commission on March 7, 2000, which contains a description of the
          terms, rights and provisions of the Company's Class A Preferred Share
          Purchase Rights attached to and currently trading together with shares
          of the Company's Class A Common Stock, including any amendment or
          report filed for the purpose of updating such description; and

     o    The description of the Company's Class A Common Stock contained in the
          Company's Registration Statement on Form 8-A filed with the Commission
          on July 7, 1999, including any amendment or report filed for the
          purpose of updating such description.

                                       -9-
In addition, all documents subsequently filed with the Commission by the
Company pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act on
or after the date of this Registration Statement and prior to the filing of a
post-effective amendment which indicates that all securities offered hereunder
have been sold or which deregisters all securities then remaining unsold under
this Registration Statement (other than Current Reports on Form 8-K containing
Regulation FD disclosure furnished under Item 7.01 or Results of Operations and
Financial Condition disclosure furnished under Item 2.02 and exhibits relating
to such disclosures, unless otherwise specifically stated in such Current Report
on Form 8-K), shall be deemed to be incorporated by reference in this
Registration Statement and to be part hereof from the date of filing of such
documents.

     You may request a copy of these filings, at no cost, by writing or
telephoning our Investor Relations department, at the following address:

                                  Gartner, Inc.
                               56 Top Gallant Road
                               Stamford, CT 06902
                                 (203) 316-1111

     We file annual, quarterly and special reports and other information with
the Commission. You may read and copy any documents we file at the Commission's
Public Reference Room at 450 Fifth Street, N.W., Washington, D.C. 20549. Please
call the Commission at 1-800-SEC-0330 for further information on the public
reference room. Our Commission filings are also available to the public from the
Commission's website at http://www.sec.gov.

     Our Internet address is www.gartner.com and the investor relations section
of our Web site is located at www.gartner.com/investors. We make available free
of charge, on or through the investor relations section of our Web site, annual
reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form
8-K and amendments to those reports filed or furnished pursuant to Section 13(a)
or 15(d) of the Exchange Act as soon as reasonably practicable after we
electronically file such material with, or furnish it to, the Commission.

                                      -10-
PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

ITEM 3. INCORPORATION OF DOCUMENTS BY REFERENCE

     The following documents and information previously filed with the
Commission by the Company are hereby incorporated in this Registration Statement
by reference:

     o    The Company's Annual Report on Form 10-K for the fiscal year ended
          December 31, 2003, filed with the Commission on March 12, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended
          March 31, 2004, filed with the Commission on May 4, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended June
          30, 2004, filed with the Commission on August 3, 2004;

     o    The Company's Quarterly Report on Form 10-Q for the quarter ended
          September 30, 2004, filed with the Commission on November 8, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          September 1, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          September 29, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          October 15, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          October 25, 2004;

     o    The Company's Current Report on Form 8-K filed with the Commission on
          November 1, 2004;

     o    The Company's Registration Statement on Form 8-A filed with the
          Commission on March 7, 2000, which contains a description of the
          terms, rights and provisions of the Company's Class A Preferred Share
          Purchase Rights attached to and currently trading together with shares
          of the Company's Class A Common Stock, including any amendment or
          report filed for the purpose of updating such description; and

     o    The description of the Company's Class A Common Stock contained in the
          Company's Registration Statement on Form 8-A filed with the Commission
          on July 7, 1999, including any amendment or report filed for the
          purpose of updating such description.

     In addition, all documents subsequently filed with the Commission by the
Registrant pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act
on or after the date of this Registration Statement and prior to the filing of a
post-effective amendment which indicates that all securities offered hereunder
have been sold or which deregisters all securities then remaining unsold under
this Registration Statement (other than Current Reports on Form 8-K containing
Regulation FD disclosure furnished under Item 7.01 or Results of Operations and
Financial Condition disclosure furnished under Item 2.02 and exhibits relating
to such

                                      II-1
disclosures, unless otherwise specifically stated in such Current Report on Form
8-K), shall be deemed to be incorporated by reference in this Registration
Statement and to be part hereof from the date of filing of such documents. Any
statement contained herein or in a document incorporated or deemed to be
incorporated by reference herein shall be deemed to be modified or superseded
for purposes of this Registration Statement to the extent that a statement
contained herein or in any other subsequently filed document which also is or is
deemed to be incorporated by reference herein modifies or supersedes such
earlier statement. Any statement so modified or superseded shall not be deemed,
except as so modified or superseded, to constitute a part of this Registration
Statement.

ITEM 4. DESCRIPTION OF SECURITIES

     Inapplicable.

ITEM 5. INTERESTS OF NAMED EXPERTS AND COUNSEL

     The validity of the securities being registered by this Registration
Statement will be passed upon by Wilson Sonsini Goodrich & Rosati, Professional
Corporation, Palo Alto, California.

ITEM 6. INDEMNIFICATION OF DIRECTORS AND OFFICERS

     Section 145 of the Delaware General Corporation Law ("Delaware Law")
provides that a corporation may indemnify a director, officer, employee or agent
made a party to an action by reason of the fact that he was a director, officer,
employee or agent of the corporation, or was serving at the request of the
corporation, against expenses actually and reasonably incurred, including
attorneys' fees, in connection with such action, if he acted in good faith and
in a manner he reasonably believed to be in, or not opposed to, the best
interests of the corporation and, with respect to any criminal action, had no
reasonable cause to believe his conduct was unlawful.

     The Company's Certificate of Incorporation limits, to the maximum extent
permitted by Delaware Law, the personal liability of a director to the
Registrant or its stockholders for monetary damages for breach of fiduciary duty
as a director. The Company's Bylaws provide that the Registrant shall indemnify
its officers and directors to the fullest extent permitted by Delaware Law
against all expense, liability and loss, including attorneys' fees, actually and
reasonably incurred and may purchase and maintain insurance against any
liability asserted and incurred by reason of serving as such, whether or not the
Registrant has the power to indemnify against such liability. The Registrant has
entered into indemnification agreements with its officers and directors
containing provisions which are in some respects broader than the specific
indemnification provisions contained in Delaware Law and which require that, to
the extent the Registrant maintains liability insurance applicable to officers
or directors, each officer and director shall be covered by such policies to the
same extent as are accorded the most favorably insured of the Company's officers
or directors, as the case may be.

ITEM 7. EXEMPTION FROM REGISTRATION CLAIMED

     The issuance of the shares being offered by the Form S-3 resale Prospectus
were deemed to be exempt from registration under the Securities Act in reliance
upon Section 4(2) of the Securities Act or Regulation D promulgated thereunder.

                                      II-2
ITEM 8. EXHIBITS

Exhibit
Number                            Description
-------   ----------------------------------------------------------------------
4.1       Amended and Restated Certificate of Incorporation of the Registrant
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2000 as filed on December 29,
          2000).

4.2       Certificate of Amendment of the Restated Certificate of Incorporation
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2001 as filed on December 28,
          2001).

4.3       Certificate of Designation, Preferences and Rights of Series A Junior
          Participating Preferred Stock and Series B Junior Participating
          Preferred Stock of the Registrant (incorporated by reference from the
          Registrant's Form 8-K dated March 1, 2000 as filed on March 7, 2000).

4.4       Amended Bylaws of the Registrant as amended through April 14, 2000
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2000 as filed on December 29,
          2000).

4.5       Form of Certificate for Class A Common Stock, Class A (incorporated by
          reference from the Registrant's Annual Report on Form 10-K for the
          year ended September 30, 2001 as filed on December 28, 2001).

4.6       Amended and Restated Rights Agreement, dated as of August 31, 2002
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2002 as filed on December 27,
          2002).

4.7       Amendment No. 1 to the Amended and Restated Rights Agreement, dated as
          of June 30, 2003 (incorporated by reference from the Registrant's
          Amendment No. 2 to Form 8-A as filed on June 30, 2003).

5.1       Opinion of Wilson Sonsini Goodrich & Rosati, Professional Corporation.

23.1      Consent of Independent Registered Public Accounting Firm.

23.2      Consent of Wilson Sonsini Goodrich & Rosati, Professional Corporation
          (included in Exhibit 5.1 to this Registration Statement).

24.1      Power of Attorney (included in the signature page of this Registration
          Statement).

ITEM 9. UNDERTAKINGS

     (a)  The undersigned Registrant hereby undertakes:

          (1) To file, during any period in which offers or sales are being
made, a post-effective amendment to this Registration Statement:

               (i) To include any prospectus required by section 10(a)(3) of the
Securities Act;

               (ii) To reflect in the prospectus any facts or events arising
after the effective date of the registration statement (or the most recent
post-effective amendment thereof) which, individually or in the aggregate,
represent a fundamental change in the information set forth in the registration
statement;

               (iii) To include any material information with respect to the
plan of distribution not previously disclosed in the registration statement or
any material change to such information in the registration statement;

                                      II-3
Provided, however, that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply if
the information required to be included in a post-effective amendment by those
paragraphs is contained in periodic reports filed by the Registrant pursuant to
section 13 or section 15(d) of the Exchange Act that are incorporated by
reference in the registration statement.

          (2) That, for the purpose of determining any liability under the
Securities Act, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

          (3) To remove from registration by means of a post-effective amendment
any of the securities being registered which remain unsold at the termination of
the offering.

     (b) The undersigned Registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to section 13(a) or section 15(d) of the
Exchange Act (and, where applicable, each filing of an employee benefit plan's
annual report pursuant to section 15(d) of the Exchange Act) that is
incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the
offering of such securities at that time shall be deemed to be the initial bona
fide offering thereof.

     (c) Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Act and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by the registrant of expenses incurred
or paid by a director, officer or controlling person of the registrant in the
successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

                                      II-4
SIGNATURES

THE REGISTRANT

     Pursuant to the requirements of the Securities Act, the Registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8/S-3 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Stamford, state of Connecticut on this 23 day of
November, 2004.

                                               GARTNER, INC.
                                               (Registrant)

                                               By: /s/ Christopher Lafond
                                                   -------------------------
                                                   Christopher Lafond
                                                   Executive Vice President,
                                                   Chief Financial Officer

                                POWER OF ATTORNEY

     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Eugene A. Hall and Christopher Lafond,
and each of them, his true and lawful attorneys-in-fact, each with the power of
substitution, for him and his name, place and stead, in any and all capacities,
to sign any and all amendments (including post-effective amendments) to this
Registration Statement, and to sign any registration statement for the same
offering covered by this Registration Statement that are to be effective upon
filing pursuant to Rule 462(b) promulgated under the Securities Act, as amended,
and all post-effective amendments thereto, and to file the same, with all
exhibits thereto in all documents in connection therewith, with the Commission,
granting unto said attorneys-in-fact and agents, and each of them, full power
and authority to do and perform each and every act and thing requisite and
necessary to be done in and about the premises, as fully to all intents and
purposes as he might or could do in person, hereby ratifying and confirming all
that such attorneys-in-fact and agents or any of them, or his or their
substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

     Pursuant to the requirements of the Securities Act, this Registration
Statement has been signed by the following persons in the capacities and on the
dates indicated.
Signature                                        Title                              Date
--------------------------------------     -----------------------------------------------    -----------------
/s/ Eugene A. Hall                         Director and Chief Executive Officer (Principal    November 23, 2004
--------------------------------------     Executive Officer)
Eugene A. Hall

/s/ Christopher Lafond                     Executive Vice President, Chief Financial          November 23, 2004
--------------------------------------     Officer (Principal Financial and Accounting
Christopher Lafond                         Officer)
II-5
Signature                                        Title                              Date
--------------------------------------     -----------------------------------------------    -----------------
/s/ Anne Sutherland Fuchs                  Director                                           November 23, 2004
--------------------------------------
Anne Sutherland Fuchs

/s/ William O. Grabe                       Director                                           November 23, 2004
--------------------------------------
William O. Grabe

/s/ Max D. Hopper                          Director                                           November 23, 2004
--------------------------------------
Max D. Hopper

/s/ Glenn H. Hutchins                      Director                                           November 23, 2004
--------------------------------------
Glenn H. Hutchins

/s/ Stephen G. Pagliuca                    Director                                           November 23, 2004
--------------------------------------
Stephen G. Pagliuca

/s/ James C. Smith                         Chairman of the Board                              November 23, 2004
--------------------------------------
James C. Smith

/s/ Michael J. Bingle                      Director                                           November 23, 2004
--------------------------------------
Michael J. Bingle

/s/ Jeffrey W. Ubben                       Director                                           November 23, 2004
--------------------------------------
Jeffrey W. Ubben

/s/ Maynard G. Webb, Jr.                   Director                                           November 23, 2004
--------------------------------------
Maynard G. Webb, Jr.
II-6
EXHIBIT INDEX

Exhibit
Number                            Description
-------   ----------------------------------------------------------------------
4.1       Amended and Restated Certificate of Incorporation of the Registrant
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2000 as filed on December 29,
          2000).

4.2       Certificate of Amendment of the Restated Certificate of Incorporation
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2001 as filed on December 28,
          2001).

4.3       Certificate of Designation, Preferences and Rights of Series A Junior
          Participating Preferred Stock and Series B Junior Participating
          Preferred Stock of the Registrant (incorporated by reference from the
          Registrant's Form 8-K dated March 1, 2000 as filed on March 7, 2000).

4.4       Amended Bylaws of the Registrant as amended through April 14, 2000
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2000 as filed on December 29,
          2000).

4.5       Form of Certificate for Class A Common Stock, Class A (incorporated by
          reference from the Registrant's Annual Report on Form 10-K for the
          year ended September 30, 2001 as filed on December 28, 2001).

4.6       Amended and Restated Rights Agreement, dated as of August 31, 2002
          (incorporated by reference from the Registrant's Annual Report on Form
          10-K for the year ended September 30, 2002 as filed on December 27,
          2002).

4.7       Amendment No. 1 to the Amended and Restated Rights Agreement, dated as
          of June 30, 2003 (incorporated by reference from the Registrant's
          Amendment No. 2 to Form 8-A as filed on June 30, 2003).

5.1       Opinion of Wilson Sonsini Goodrich & Rosati, Professional Corporation.

23.1      Consent of Independent Registered Public Accounting Firm.

23.2      Consent of Wilson Sonsini Goodrich & Rosati, Professional Corporation
          (included in Exhibit 5.1 to this Registration Statement).

24.1      Power of Attorney (included in the signature page of this Registration
          Statement).

                                      II-7