As filed with the Securities and Exchange Commission on June 16, 2000
                                                         Registration No.  333 -
--------------------------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                  -------------

                                    FORM S-8
                             REGISTRATION STATEMENT

                                      UNDER

                           THE SECURITIES ACT OF 1933
                                  -------------
                                   PSINET INC.

             (Exact name of registrant as specified in its charter)

          New York                                          16-1353600
 (State or other jurisdiction of                           (I.R.S. Employer
 incorporation or organization)                          Identification No.)

  44983 Knoll Square, Ashburn, Virginia                         20147
(Address of principal executive offices)                      (Zip Code)

                         EXECUTIVE STOCK INCENTIVE PLAN

                         STRATEGIC STOCK INCENTIVE PLAN

              OPTION AGREEMENT BETWEEN REGISTRANT AND SUSAN DISESA

                            (Full title of the plans)

                             Kathleen B. Horne, Esq.
                    Senior Vice President and General Counsel

                                   PSINet Inc.

                   44983 Knoll Square, Ashburn, Virginia 20147

                     (Name and address of agent for service)

          Telephone No.: (703) 726-4100 / Facsimile No.: (703) 726-4265
          (Telephone number, including area code, of agent for service)
                                  -------------

                                    Copy to:
                          Richard F. Langan, Jr., Esq.
                                Nixon Peabody LLP
                  437 Madison Avenue, New York, New York 10022
           Telephone No.: (212) 940-3140/Facsimile No.: (212) 940-9940
                                  -------------

<TABLE>

<CAPTION>
---------------------------------------------------------------------------------------------------------------------

                                          CALCULATION OF REGISTRATION FEE
-------------------------------- -------------------- -------------------- ---------------------- -------------------
                                                       Proposed maximum      Proposed maximum

      Title of securities           Amount to be        offering price      Aggregate offering        Amount of
       to be registered            registered (1)        per share (2)           price (2)         registration fee
-------------------------------- -------------------- -------------------- ---------------------- -------------------
<S>                              <C>                  <C>                 <C>                    <C>

Common Stock, $.01 par value     25,000,000 shares    $30.25              $756,250,000           $199,650
-------------------------------- -------------------- -------------------- ---------------------- -------------------

<FN>

         (1) Represents (i) 12,000,000 shares issuable upon the exercise of
options granted or to be granted under the Executive Stock Incentive Plan, (ii)
13,000,000 shares issuable upon the exercise of options granted or to be granted
under the Strategic Stock Incentive Plan, and (iii) pursuant to Rule 416(a) of
the Securities Act of 1933, such indeterminate number of shares as may be issued
by reason of any stock split, stock dividend, recapitalization or similar
transaction effected without the receipt of consideration which results in an
increase in the number of outstanding shares of PSINet common stock.

         (2) Estimated in accordance with Rule 457(c) under the Securities Act
of 1933 solely for the purpose of calculating the registration fee. The
computation is based upon the average of the high and low prices of our common
stock as reported on the Nasdaq Stock Market's National Market on June 13, 2000.

</FN>
</TABLE>

                              --------------------

                        STATEMENT PURSUANT TO RULE 429(B)

THE PROSPECTUS CONTAINED IN THIS REGISTRATION STATEMENT IS A COMBINED PROSPECTUS
 WHICH ALSO COVERS THE DISESA OPTIONS WHICH WERE REGISTERED UNDER REGISTRATION
                     STATEMENT ON FORM S-8 (NO. 333-92021)


<PAGE>


                                     PART I.

                  INFORMATION REQUIRED IN THE 10(a) PROSPECTUS

                                EXPLANATORY NOTE

         At our 2000 Annual Meeting of Shareholders held on May 15, 2000, our
shareholders approved amendments to our Executive Stock Incentive Plan and our
Strategic Stock Incentive Plan to increase the number of shares available for
issuance under each of the plans. This registration statement on Form S-8
relates to the registration of additional securities of the same class as other
securities of which our registration statement on Form S-8 filed on December 3,
1999 (No. 333-92021) is effective consisting of up to 12,000,000 additional
shares of our common stock, par value $.01 per share, issuable pursuant to our
Executive Stock Incentive Plan and up to 13,000,000 additional shares of our
common stock issuable pursuant to our Strategic Stock Incentive Plan.
Accordingly, pursuant to Instruction E to SEC Form S-8, the contents of the
following earlier registration statements are incorporated herein by reference:
(1) Registration Statement on Form S-8, relating to our Executive Stock
Incentive Plan (No. 33-99464); (2) Registration Statement on Form S-8, relating
to our Strategic Stock Incentive Plan (No. 33-99470); (3) Registration Statement
on Form S-8 (No. 333-82811); and (4) Registration Statement on Form S-8 (No.
333-92021).

         This registration statement also relates to 19,650 shares of our common
stock, as adjusted for our two-for-one common stock split in February 2000, that
may be issued to Susan DiSesa, upon the exercise of options granted to her under
an option agreement. The reoffer prospectus included herein is intended to
register for reoffer and/or resale 19,650 shares of our common stock that may be
issued to Ms. DiSesa upon the exercise of options granted to her under an option
agreement.

         Information required to be contained in the Section 10(a) prospectus is
omitted from the registration statement in accordance with Rule 428 of the
Securities and Exchange Commission issued under the Securities Act of 1933, as
amended and the Note to Part I of Form S-8.


                                      -2-

<PAGE>


REOFFER PROSPECTUS

                                   PSINET INC.

                          19,650 SHARES OF COMMON STOCK

         This prospectus relates to the offering of up to 19,650 shares of our
common stock which may be sold from time to time in one or more transactions by
Susan DiSesa, a former consultant of one of our subsidiaries. Ms. DiSesa is also
referred to as the "Selling Shareholder." We will not receive any of the
proceeds from the sale of these shares.

         The Selling Shareholder will sell the shares offered hereby at prices
which are current when the sales take place or at other prices upon which the
parties agree. The Selling Shareholder may or may not use brokers and dealers in
these transactions, but will pay brokerage fees or commissions, if relevant. We
will pay all of the expenses associated with the registration of the shares and
this prospectus.

         Our common stock is listed for trading on the Nasdaq Stock Market's
National Market under the symbol "PSIX." On June 14, 2000, the last reported
sale price of our common stock was $30.13.



                  --------------------------------------------



  Investment in our common stock involves risk. See "Risk Factors" incorporated
                              herein by reference.

    Neither the Securities and Exchange Commission nor any state securities
 commission has approved or disapproved these securities, or determined if this
  prospectus is truthful or complete. Any representation to the contrary is a
                               criminal offense.

                  --------------------------------------------



                  The date of this prospectus is June 16, 2000


                                      -3-

<PAGE>


                               PROSPECTUS SUMMARY

         This summary highlights some information from this prospectus. Because
this is a summary, it may not contain all of the information that may be
important to you. You should read the entire prospectus, including the Risk
Factors incorporated by reference in this prospectus before making an investment
decision.

                                   THE COMPANY

         We are a leading global provider of Internet and eCommerce solutions to
businesses. With our worldwide fiber network and related optronic equipment,
multiple Internet and eCommerce hosting centers, full suite of Internet access
and eCommerce products, extensive global distribution network and global brand
name recognition, we have become an Internet Super Carrier or ISC. We offer a
robust suite of products that enable our customers to utilize the Internet
around the globe for mission critical applications carried over a worldwide
fiber optic network that is capable of transmission speeds in excess of three
terabits per second. We provide Internet connectivity and Web hosting services
to approximately 100,000 corporate customers in 28 countries. Including our
Internet service provider (ISP), carrier, small office/home office (SOHO) and
consumer businesses, we serve over 2.0 million end users around the world. We
serve approximately 90 of the 100 largest metropolitan statistical areas in the
U.S. and have a presence in the 20 largest telecommunications markets globally.

         Our services and products include dedicated, dial-up and digital
subscriber line (DSL) Internet access services connections, Web hosting and
collocation services, transaction network services, virtual private networks
(VPNs), eCommerce solutions, voice-over-Internet protocol (IP), e-mail and
managed security services. We also provide wholesale and private label network
connectivity and related services to other ISPs and telecommunications carriers
to further utilize our network capacity. We currently operate nine Internet and
eCommerce hosting centers with an aggregate of 338,000 square feet in North
America, Europe and Asia and plan to open fifteen more hosting centers having
more than 1,650,000 additional square feet.

                           --------------------------

         We are a New York corporation and our principal executive offices are
located at 44983 Knoll Square, Ashburn, Virginia 20147. Our telephone number is
(703) 726-4100.



                                   -4-

<PAGE>


                                 USE OF PROCEEDS

         The shares of common stock covered by this prospectus are being offered
by the Selling Shareholder and not by us. Consequently, we will not receive any
proceeds from the sale of these shares. However the shares that may be sold
under the prospectus include shares that the Selling Shareholder may acquire in
the future pursuant to stock options that we have granted to her. In order for
the Selling Shareholder to acquire any such shares, the Selling Shareholder will
be required to pay to us the exercise price specified in her option agreement.
We intend to use any proceeds that we receive from the exercise of such options
for working capital and general corporate purposes.

                               SELLING SHAREHOLDER

         The table below sets forth, as of the date of this prospectus or a
subsequent date if amended or supplemented, (a) the name of the Selling
Shareholder and her relationship to PSINet during the past three years; (b) the
number of shares of common stock that we have been advised that the Selling
Shareholder beneficially owns; (c) the number of shares of common stock that we
have been advised will be offered pursuant to this prospectus by the Selling
Shareholder; and (d) the amount and percentage of the common stock outstanding
to be held by the Selling Shareholder after giving effect to the offering of the
common stock covered by this prospectus. The information contained in this table
may be amended or supplemented from time to time.


<TABLE>
<CAPTION>
                                               Shares                                   Shares Beneficially
                      Relationship          Beneficially           Shares              Owned After Offering
Name                    to PSINet              Owned           Offered Hereby
-----                ---------------       ---------------    -----------------       -----------------------

                                                                                      Number        Percentage
                                                                                      -------      ------------
<S>                  <C>                   <C>                <C>                     <C>          <C>
Susan DiSesa         Former Consultant     19,650             19,650                  - 0 -        0 %

</TABLE>


                              PLAN OF DISTRIBUTION

         Any of or all of the shares may be sold from time to time to purchasers
directly by the Selling Shareholder. Alternatively, the Selling Shareholder may
from time to time offer the shares through underwriters, dealers or agents who
may receive compensation in the form of discounts, concessions or commissions
from the Selling Shareholder and/or the purchasers of shares for whom they may
act. The Selling Shareholder and any such underwriters, dealers or agents that
participate in the distribution of Shares may be deemed to be underwriters under
the Securities Act of 1933, as amended (the "Securities Act"). Any profit on the
sale of the shares by them and any discounts, commissions or concessions
received by them may be deemed to be underwriting discounts and commissions
under the Securities Act. To the extent required, at the time a particular offer
of shares is made, a supplement to this prospectus will be distributed which
will set forth the number of shares being offered and the terms of the offering.
These terms will include the name or names of any underwriters, dealers or
agents, any discounts, commissions and other items constituting compensation
from the Selling Shareholder and any discounts, commissions or concessions
allowed or reallowed or paid to dealers, including the proposed selling price to
the public.

         The shares may be sold from time to time in one or more transactions at
a fixed offering price, which may be changed, or at varying prices determined at
the time of sale or at negotiated prices.


                                      -5-

<PAGE>


         In order to comply with certain states' securities laws, if applicable,
the shares will be sold in such jurisdictions only through registered or
licensed brokers or dealers. In certain states the shares may not be sold unless
the shares have been registered or qualified for sale in such state or an
exemption from registration or qualification is available and is met.

                                  LEGAL MATTERS

         The validity of the securities offered hereby will be passed upon by
Nixon Peabody LLP, New York, New York, counsel for PSINet. Certain attorneys
with Nixon Peabody LLP currently own in the aggregate less than one percent of
our common stock.

                                     EXPERTS

         The consolidated financial statements of PSINet Inc. as of December 31,
1999 and 1998 and for each of the three years in the period ended December 31,
1999 incorporated by reference in this prospectus have been so incorporated in
reliance on the report of PricewaterhouseCoopers LLP, independent accountants,
given on the authority of said firm as experts in auditing and accounting.

                       WHERE YOU CAN FIND MORE INFORMATION

         We file annual, quarterly and special reports, proxy statements and
other information with the Securities and Exchange Commission. You may read and
copy any reports, statements or other information that we file with the
Securities and Exchange Commission at the Securities and Exchange Commission's
public reference room at the following location:

                              Public Reference Room
                             450 Fifth Street, N.W.
                                    Room 1024
                             Washington, D.C. 20549

         Please call the Securities and Exchange Commission at 1-800-SEC-0330
for further information on the public reference rooms. These Securities and
Exchange Commission filings are also available to the public from commercial
document retrieval services and at the Internet world wide web site maintained
by the Securities and Exchange Commission at "http://www.sec.gov." Reports,
proxy statements and other information pertaining to PSINet are also available
for inspection at the offices of The Nasdaq Stock Market, which is located at
1735 K Street, N.W., Washington, D.C. 20006.

         We may "incorporate by reference" information into this prospectus,
which means that we can disclose important information to you by referring you
to other documents filed with the Securities and Exchange Commission. The
information incorporated by reference is considered part of this document,
except for any information superseded by information contained directly in this
prospectus or in later filed documents incorporated by reference in this
prospectus.

         This prospectus incorporates by reference the documents set forth below
under the caption "Documents Incorporated by Reference" that we have previously
filed with the Securities and Exchange Commission. These documents contain
important business and financial information about us that is not included in or
delivered with this prospectus.

         We may already have sent you some of the documents incorporated by
reference, but you can obtain any of them through us, the Securities and
Exchange Commission or the Securities and Exchange


                                      -6-

<PAGE>


Commission's Internet web site as described above. Documents incorporated by
reference are available from us without charge, excluding all exhibits, except
that if we have specifically incorporated by reference an exhibit in this
prospectus, the exhibit will also be provided without charge. You may obtain
documents incorporated by reference in this prospectus by requesting them in
writing or by telephone from us at the following address:

                                   PSINET INC.
                               44983 Knoll Square
                             Ashburn, Virginia 20147
                          Attention: Investor Relations
                            Telephone: (703) 726-1577
                            Facsimile: (703) 726-4261
                        email: investor-relations@psi.com

         You should rely only on the information contained or incorporated by
reference in this prospectus. We have not authorized anyone to provide you with
information that is different from what is contained in this prospectus. This
prospectus is dated June 15, 2000. You should not assume that the information
contained in this prospectus is accurate as of any date other than that date.


                                      -7-

<PAGE>


                       DOCUMENTS INCORPORATED BY REFERENCE

         The SEC allows us to "incorporate by reference" the information we file
with them, which means that we can disclose important information to you by
referring you to those documents. The information incorporated by reference is
an important part of this prospectus, and information that we file later with
the SEC will automatically update and supersede this information. We are
incorporating by reference in this prospectus the following documents:

         (1) Annual report on Form 10-K for the fiscal year ended December 31,
             1999. This report contains:

             o audited consolidated balance sheets for PSINet and its
               subsidiaries as of December 31, 1999 and 1998; and

             o audited consolidated statements of operations, of changes in
               shareholders' equity and of cash flows for the years ended
               December 31, 1999, 1998 and 1997.

         (2) Quarterly report on Form 10-Q for the quarter ended March 31, 2000.

         (3) Current reports on Form 8-K dated:

             o January 10, 2000

             o January 16, 2000

             o January 24, 2000

             o January 27, 2000

             o January 26, 2000

             o February 1, 2000

             o March 22, 2000

             o June 5, 2000

             o June 13, 2000

             o June 15, 2000

         (4) The Joint Proxy Statement/Prospectus contained in Amendment No. 1
             to the Registration Statement on Form S-4 (registration no.
             333-34802) filed with the Securities and Exchange Commission on May
             12, 2000.

         (5) Our registration statement on Form 8-A dated April 7, 1995, as
             amended (registration no. 0-25812).

         (6) Our registration statement on Form 8-A dated June 4, 1996, as
             amended (registration no. 0-25812).

         We are also incorporating by reference in this registration statement
all reports and other documents that we may file with the Securities and
Exchange Commission under Section 13(a),13(c), 14 or 15(d) of the Exchange Act
subsequent to the date of this registration statement and prior to the filing of
a post-effective amendment which indicates that all securities offered hereby
have been sold or which deregisters all securities remaining. These reports and
documents will be incorporated by reference


                                      -8-

<PAGE>

in and considered to be a part of this registration statement as of the date of
filing of such reports and documents.

         Any statement contained in this prospectus or in a document which is
incorporated by reference herein will be modified or superseded for purposes of
this prospectus to the extent that a statement in any document that we file
after the date of this prospectus that also is incorporated by reference herein
modifies or supersedes such prior statement. Any such statement so modified or
superseded will not, except as so modified or superseded, constitute a part of
this prospectus.

         This prospectus incorporates by reference documents which are not
presented in this prospectus or delivered to you with it. You may request, and
we will send to you, without charge, copies of these documents, other than
exhibits to these documents, which we will send to you for a reasonable fee.
Requests should be directed to the Office of the Secretary, PSINet Inc., 44983
Knoll Square, Ashburn, Virginia 20147 (telephone (703) 726-4100).

                      DISCLOSURE OF COMMISSION POSITION ON
                 INDEMNIFICATION FOR SECURITIES ACT LIABILITIES

         Insofar as indemnification for liabilities arising under the Securities
Act of 1933 may be permitted to directors, officers, and controlling persons of
PSINet pursuant to the foregoing provisions, PSINet has been informed that in
the opinion of the Securities and Exchange Commission such indemnification is
against public policy as expressed in the Securities Act of 1933 and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by registrant of expenses incurred 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, 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 of 1933 and will be governed by the
final adjudication of such issue.

         Except to the extent set forth herein, there is no charter provision,
by-law, contract, arrangement or statute pursuant to which any director or
officer of registrant is indemnified in any manner against any liability which
he may incur in his capacity as such.


                                      -9-

<PAGE>


                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized in the City of Ashburn, Commonwealth of Virginia on June 15, 2000.

                           PSINET INC.


                           By: /s/ William L. Schrader
                             -------------------------------
                             William L. Schrader, Chairman
                             and Chief Executive Officer


                                POWER OF ATTORNEY

         KNOW ALL MEN BY THESE PRESENTS, that each person whose signature
appears below hereby constitutes and appoints William L. Schrader, Harold S.
Wills, David N. Kunkel and Kathleen B. Horne, and each or any of them, his true
and lawful attorney-in-fact and agent, with full power of substitution and
resubstitution, for him and in his name, place and stead, in any and all
capacities, to sign any registration statement filed pursuant to Rule 462(b)
under the Securities Act of 1933 and any and all amendments (including
post-effective amendments) to this registration statement and to any
registration statement filed pursuant to Rule 462(b), and to file same, with all
exhibits thereto and other documents in connection therewith, with the
Securities and Exchange Commission, granting unto each said attorney-in-fact and
agent full power and authority to do and perform each and every act and thing
requisite and necessary to be done in and about the foregoing, as fully to all
intents and purposes as he might or could do in person, hereby ratifying and
confirming all that said attorney-in-fact and agent or either of them, or their
or his substitute or substitutes, may lawfully do or cause to be done by virtue
hereof.

         Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the dates indicated.

       Name                            Title                          Date
       -----                           -----                         ------

/s/ William L. Schrader        Chairman, Chief Executive
------------------------      Officer and Director (Principal     June 15, 2000
William L. Schrader               Executive Officer)


/s/ Harold S. Wills            President, Chief Operating         June 15, 2000
------------------------          Officer and Director
Harold S. Wills


/s/ David N. Kunkel                 Vice Chairman,
------------------------        Executive Vice President          June 15, 2000
David N. Kunkel                      and Director

                                      -10-

<PAGE>


/s/ Jorge R. Forgues          Vice President and Acting Chief
------------------------             Financial Officer            June 15, 2000
Jorge R. Forgues                    (Principal Financial
                                  and Accounting Officer)


/s/ William H. Baumer                    Director                 June 15, 2000
------------------------
William H. Baumer



------------------------                 Director                 June __, 2000
Ralph J. Swett


                                         Director                 June __, 2000
------------------------
Ian P. Sharp


                                      -11-

<PAGE>


                                  EXHIBIT INDEX

Exhibit
 No.      Description                             Location
-------   ------------                            ---------

4.1      Executive Stock Incentive Plan,        Incorporated by reference to
         as amended                             Exhibit B to PSINet's Proxy
                                                Statement on Schedule 14A filed
                                                with the Securities and Exchange
                                                Commission on April 7, 2000
                                                (File No.0-25812)

4.2      Strategic Stock Incentive Plan,        Incorporated by reference to
         as amended                             Exhibit B to PSINet's Proxy
                                                Statement on Schedule 14A filed
                                                with the Securities and Exchange
                                                Commission on April 7, 2000
                                                (File No.0-25812)

5.1      Opinion of Nixon Peabody LLP           Filed herewith

23.1     Consent of Nixon Peabody LLP           Contained in opinion filed as
                                                Exhibit 5.1 to this Registration
                                                Statement

23.2     Consent of PricewaterhouseCoopers LLP  Filed herewith


                                      -12-
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As filed with the Securities and Exchange Commission on June 16, 2000
                                                         Registration No.  333 -
--------------------------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                  -------------

                                    FORM S-8
                             REGISTRATION STATEMENT

                                      UNDER

                           THE SECURITIES ACT OF 1933
                                  -------------
                                   PSINET INC.

             (Exact name of registrant as specified in its charter)

          New York                                          16-1353600
 (State or other jurisdiction of                           (I.R.S. Employer
 incorporation or organization)                          Identification No.)

  44983 Knoll Square, Ashburn, Virginia                         20147
(Address of principal executive offices)                      (Zip Code)

                         EXECUTIVE STOCK INCENTIVE PLAN

                         STRATEGIC STOCK INCENTIVE PLAN

              OPTION AGREEMENT BETWEEN REGISTRANT AND SUSAN DISESA

                            (Full title of the plans)

                             Kathleen B. Horne, Esq.
                    Senior Vice President and General Counsel

                                   PSINet Inc.

                   44983 Knoll Square, Ashburn, Virginia 20147

                     (Name and address of agent for service)

          Telephone No.: (703) 726-4100 / Facsimile No.: (703) 726-4265
          (Telephone number, including area code, of agent for service)
                                  -------------

                                    Copy to:
                          Richard F. Langan, Jr., Esq.
                                Nixon Peabody LLP
                  437 Madison Avenue, New York, New York 10022
           Telephone No.: (212) 940-3140/Facsimile No.: (212) 940-9940
                                  -------------
---------------------------------------------------------------------------------------------------------------------

                                          CALCULATION OF REGISTRATION FEE
-------------------------------- -------------------- -------------------- ---------------------- -------------------
                                                       Proposed maximum      Proposed maximum

      Title of securities           Amount to be        offering price      Aggregate offering        Amount of
       to be registered            registered (1)        per share (2)           price (2)         registration fee
-------------------------------- -------------------- -------------------- ---------------------- -------------------
Common Stock, $.01 par value     25,000,000 shares    $30.25              $756,250,000           $199,650
-------------------------------- -------------------- -------------------- ---------------------- -------------------
(1) Represents (i) 12,000,000 shares issuable upon the exercise of
options granted or to be granted under the Executive Stock Incentive Plan, (ii)
13,000,000 shares issuable upon the exercise of options granted or to be granted
under the Strategic Stock Incentive Plan, and (iii) pursuant to Rule 416(a) of
the Securities Act of 1933, such indeterminate number of shares as may be issued
by reason of any stock split, stock dividend, recapitalization or similar
transaction effected without the receipt of consideration which results in an
increase in the number of outstanding shares of PSINet common stock.

         (2) Estimated in accordance with Rule 457(c) under the Securities Act
of 1933 solely for the purpose of calculating the registration fee. The
computation is based upon the average of the high and low prices of our common
stock as reported on the Nasdaq Stock Market's National Market on June 13, 2000.
--------------------

                        STATEMENT PURSUANT TO RULE 429(B)

THE PROSPECTUS CONTAINED IN THIS REGISTRATION STATEMENT IS A COMBINED PROSPECTUS
 WHICH ALSO COVERS THE DISESA OPTIONS WHICH WERE REGISTERED UNDER REGISTRATION
                     STATEMENT ON FORM S-8 (NO. 333-92021)
PART I.

                  INFORMATION REQUIRED IN THE 10(a) PROSPECTUS

                                EXPLANATORY NOTE

         At our 2000 Annual Meeting of Shareholders held on May 15, 2000, our
shareholders approved amendments to our Executive Stock Incentive Plan and our
Strategic Stock Incentive Plan to increase the number of shares available for
issuance under each of the plans. This registration statement on Form S-8
relates to the registration of additional securities of the same class as other
securities of which our registration statement on Form S-8 filed on December 3,
1999 (No. 333-92021) is effective consisting of up to 12,000,000 additional
shares of our common stock, par value $.01 per share, issuable pursuant to our
Executive Stock Incentive Plan and up to 13,000,000 additional shares of our
common stock issuable pursuant to our Strategic Stock Incentive Plan.
Accordingly, pursuant to Instruction E to SEC Form S-8, the contents of the
following earlier registration statements are incorporated herein by reference:
(1) Registration Statement on Form S-8, relating to our Executive Stock
Incentive Plan (No. 33-99464); (2) Registration Statement on Form S-8, relating
to our Strategic Stock Incentive Plan (No. 33-99470); (3) Registration Statement
on Form S-8 (No. 333-82811); and (4) Registration Statement on Form S-8 (No.
333-92021).

         This registration statement also relates to 19,650 shares of our common
stock, as adjusted for our two-for-one common stock split in February 2000, that
may be issued to Susan DiSesa, upon the exercise of options granted to her under
an option agreement. The reoffer prospectus included herein is intended to
register for reoffer and/or resale 19,650 shares of our common stock that may be
issued to Ms. DiSesa upon the exercise of options granted to her under an option
agreement.

         Information required to be contained in the Section 10(a) prospectus is
omitted from the registration statement in accordance with Rule 428 of the
Securities and Exchange Commission issued under the Securities Act of 1933, as
amended and the Note to Part I of Form S-8.

                                      -2-
REOFFER PROSPECTUS

                                   PSINET INC.

                          19,650 SHARES OF COMMON STOCK

         This prospectus relates to the offering of up to 19,650 shares of our
common stock which may be sold from time to time in one or more transactions by
Susan DiSesa, a former consultant of one of our subsidiaries. Ms. DiSesa is also
referred to as the "Selling Shareholder." We will not receive any of the
proceeds from the sale of these shares.

         The Selling Shareholder will sell the shares offered hereby at prices
which are current when the sales take place or at other prices upon which the
parties agree. The Selling Shareholder may or may not use brokers and dealers in
these transactions, but will pay brokerage fees or commissions, if relevant. We
will pay all of the expenses associated with the registration of the shares and
this prospectus.

         Our common stock is listed for trading on the Nasdaq Stock Market's
National Market under the symbol "PSIX." On June 14, 2000, the last reported
sale price of our common stock was $30.13.

                  --------------------------------------------

  Investment in our common stock involves risk. See "Risk Factors" incorporated
                              herein by reference.

    Neither the Securities and Exchange Commission nor any state securities
 commission has approved or disapproved these securities, or determined if this
  prospectus is truthful or complete. Any representation to the contrary is a
                               criminal offense.

                  --------------------------------------------

                  The date of this prospectus is June 16, 2000

                                      -3-
PROSPECTUS SUMMARY

         This summary highlights some information from this prospectus. Because
this is a summary, it may not contain all of the information that may be
important to you. You should read the entire prospectus, including the Risk
Factors incorporated by reference in this prospectus before making an investment
decision.

                                   THE COMPANY

         We are a leading global provider of Internet and eCommerce solutions to
businesses. With our worldwide fiber network and related optronic equipment,
multiple Internet and eCommerce hosting centers, full suite of Internet access
and eCommerce products, extensive global distribution network and global brand
name recognition, we have become an Internet Super Carrier or ISC. We offer a
robust suite of products that enable our customers to utilize the Internet
around the globe for mission critical applications carried over a worldwide
fiber optic network that is capable of transmission speeds in excess of three
terabits per second. We provide Internet connectivity and Web hosting services
to approximately 100,000 corporate customers in 28 countries. Including our
Internet service provider (ISP), carrier, small office/home office (SOHO) and
consumer businesses, we serve over 2.0 million end users around the world. We
serve approximately 90 of the 100 largest metropolitan statistical areas in the
U.S. and have a presence in the 20 largest telecommunications markets globally.

         Our services and products include dedicated, dial-up and digital
subscriber line (DSL) Internet access services connections, Web hosting and
collocation services, transaction network services, virtual private networks
(VPNs), eCommerce solutions, voice-over-Internet protocol (IP), e-mail and
managed security services. We also provide wholesale and private label network
connectivity and related services to other ISPs and telecommunications carriers
to further utilize our network capacity. We currently operate nine Internet and
eCommerce hosting centers with an aggregate of 338,000 square feet in North
America, Europe and Asia and plan to open fifteen more hosting centers having
more than 1,650,000 additional square feet.

                           --------------------------

         We are a New York corporation and our principal executive offices are
located at 44983 Knoll Square, Ashburn, Virginia 20147. Our telephone number is
(703) 726-4100.

                                   -4-
USE OF PROCEEDS

         The shares of common stock covered by this prospectus are being offered
by the Selling Shareholder and not by us. Consequently, we will not receive any
proceeds from the sale of these shares. However the shares that may be sold
under the prospectus include shares that the Selling Shareholder may acquire in
the future pursuant to stock options that we have granted to her. In order for
the Selling Shareholder to acquire any such shares, the Selling Shareholder will
be required to pay to us the exercise price specified in her option agreement.
We intend to use any proceeds that we receive from the exercise of such options
for working capital and general corporate purposes.

                               SELLING SHAREHOLDER

         The table below sets forth, as of the date of this prospectus or a
subsequent date if amended or supplemented, (a) the name of the Selling
Shareholder and her relationship to PSINet during the past three years; (b) the
number of shares of common stock that we have been advised that the Selling
Shareholder beneficially owns; (c) the number of shares of common stock that we
have been advised will be offered pursuant to this prospectus by the Selling
Shareholder; and (d) the amount and percentage of the common stock outstanding
to be held by the Selling Shareholder after giving effect to the offering of the
common stock covered by this prospectus. The information contained in this table
may be amended or supplemented from time to time.
Shares                                   Shares Beneficially
                      Relationship          Beneficially           Shares              Owned After Offering
Name                    to PSINet              Owned           Offered Hereby
-----                ---------------       ---------------    -----------------       -----------------------

                                                                                      Number        Percentage
                                                                                      -------      ------------
Susan DiSesa         Former Consultant     19,650             19,650                  - 0 -        0 %
PLAN OF DISTRIBUTION

         Any of or all of the shares may be sold from time to time to purchasers
directly by the Selling Shareholder. Alternatively, the Selling Shareholder may
from time to time offer the shares through underwriters, dealers or agents who
may receive compensation in the form of discounts, concessions or commissions
from the Selling Shareholder and/or the purchasers of shares for whom they may
act. The Selling Shareholder and any such underwriters, dealers or agents that
participate in the distribution of Shares may be deemed to be underwriters under
the Securities Act of 1933, as amended (the "Securities Act"). Any profit on the
sale of the shares by them and any discounts, commissions or concessions
received by them may be deemed to be underwriting discounts and commissions
under the Securities Act. To the extent required, at the time a particular offer
of shares is made, a supplement to this prospectus will be distributed which
will set forth the number of shares being offered and the terms of the offering.
These terms will include the name or names of any underwriters, dealers or
agents, any discounts, commissions and other items constituting compensation
from the Selling Shareholder and any discounts, commissions or concessions
allowed or reallowed or paid to dealers, including the proposed selling price to
the public.

         The shares may be sold from time to time in one or more transactions at
a fixed offering price, which may be changed, or at varying prices determined at
the time of sale or at negotiated prices.

                                      -5-
In order to comply with certain states' securities laws, if applicable,
the shares will be sold in such jurisdictions only through registered or
licensed brokers or dealers. In certain states the shares may not be sold unless
the shares have been registered or qualified for sale in such state or an
exemption from registration or qualification is available and is met.

                                  LEGAL MATTERS

         The validity of the securities offered hereby will be passed upon by
Nixon Peabody LLP, New York, New York, counsel for PSINet. Certain attorneys
with Nixon Peabody LLP currently own in the aggregate less than one percent of
our common stock.

                                     EXPERTS

         The consolidated financial statements of PSINet Inc. as of December 31,
1999 and 1998 and for each of the three years in the period ended December 31,
1999 incorporated by reference in this prospectus have been so incorporated in
reliance on the report of PricewaterhouseCoopers LLP, independent accountants,
given on the authority of said firm as experts in auditing and accounting.

                       WHERE YOU CAN FIND MORE INFORMATION

         We file annual, quarterly and special reports, proxy statements and
other information with the Securities and Exchange Commission. You may read and
copy any reports, statements or other information that we file with the
Securities and Exchange Commission at the Securities and Exchange Commission's
public reference room at the following location:

                              Public Reference Room
                             450 Fifth Street, N.W.
                                    Room 1024
                             Washington, D.C. 20549

         Please call the Securities and Exchange Commission at 1-800-SEC-0330
for further information on the public reference rooms. These Securities and
Exchange Commission filings are also available to the public from commercial
document retrieval services and at the Internet world wide web site maintained
by the Securities and Exchange Commission at "http://www.sec.gov." Reports,
proxy statements and other information pertaining to PSINet are also available
for inspection at the offices of The Nasdaq Stock Market, which is located at
1735 K Street, N.W., Washington, D.C. 20006.

         We may "incorporate by reference" information into this prospectus,
which means that we can disclose important information to you by referring you
to other documents filed with the Securities and Exchange Commission. The
information incorporated by reference is considered part of this document,
except for any information superseded by information contained directly in this
prospectus or in later filed documents incorporated by reference in this
prospectus.

         This prospectus incorporates by reference the documents set forth below
under the caption "Documents Incorporated by Reference" that we have previously
filed with the Securities and Exchange Commission. These documents contain
important business and financial information about us that is not included in or
delivered with this prospectus.

         We may already have sent you some of the documents incorporated by
reference, but you can obtain any of them through us, the Securities and
Exchange Commission or the Securities and Exchange

                                      -6-
Commission's Internet web site as described above. Documents incorporated by
reference are available from us without charge, excluding all exhibits, except
that if we have specifically incorporated by reference an exhibit in this
prospectus, the exhibit will also be provided without charge. You may obtain
documents incorporated by reference in this prospectus by requesting them in
writing or by telephone from us at the following address:

                                   PSINET INC.
                               44983 Knoll Square
                             Ashburn, Virginia 20147
                          Attention: Investor Relations
                            Telephone: (703) 726-1577
                            Facsimile: (703) 726-4261
                        email: investor-relations@psi.com

         You should rely only on the information contained or incorporated by
reference in this prospectus. We have not authorized anyone to provide you with
information that is different from what is contained in this prospectus. This
prospectus is dated June 15, 2000. You should not assume that the information
contained in this prospectus is accurate as of any date other than that date.

                                      -7-
DOCUMENTS INCORPORATED BY REFERENCE

         The SEC allows us to "incorporate by reference" the information we file
with them, which means that we can disclose important information to you by
referring you to those documents. The information incorporated by reference is
an important part of this prospectus, and information that we file later with
the SEC will automatically update and supersede this information. We are
incorporating by reference in this prospectus the following documents:

         (1) Annual report on Form 10-K for the fiscal year ended December 31,
             1999. This report contains:

             o audited consolidated balance sheets for PSINet and its
               subsidiaries as of December 31, 1999 and 1998; and

             o audited consolidated statements of operations, of changes in
               shareholders' equity and of cash flows for the years ended
               December 31, 1999, 1998 and 1997.

         (2) Quarterly report on Form 10-Q for the quarter ended March 31, 2000.

         (3) Current reports on Form 8-K dated:

             o January 10, 2000

             o January 16, 2000

             o January 24, 2000

             o January 27, 2000

             o January 26, 2000

             o February 1, 2000

             o March 22, 2000

             o June 5, 2000

             o June 13, 2000

             o June 15, 2000

         (4) The Joint Proxy Statement/Prospectus contained in Amendment No. 1
             to the Registration Statement on Form S-4 (registration no.
             333-34802) filed with the Securities and Exchange Commission on May
             12, 2000.

         (5) Our registration statement on Form 8-A dated April 7, 1995, as
             amended (registration no. 0-25812).

         (6) Our registration statement on Form 8-A dated June 4, 1996, as
             amended (registration no. 0-25812).

         We are also incorporating by reference in this registration statement
all reports and other documents that we may file with the Securities and
Exchange Commission under Section 13(a),13(c), 14 or 15(d) of the Exchange Act
subsequent to the date of this registration statement and prior to the filing of
a post-effective amendment which indicates that all securities offered hereby
have been sold or which deregisters all securities remaining. These reports and
documents will be incorporated by reference

                                      -8-
in and considered to be a part of this registration statement as of the date of
filing of such reports and documents.

         Any statement contained in this prospectus or in a document which is
incorporated by reference herein will be modified or superseded for purposes of
this prospectus to the extent that a statement in any document that we file
after the date of this prospectus that also is incorporated by reference herein
modifies or supersedes such prior statement. Any such statement so modified or
superseded will not, except as so modified or superseded, constitute a part of
this prospectus.

         This prospectus incorporates by reference documents which are not
presented in this prospectus or delivered to you with it. You may request, and
we will send to you, without charge, copies of these documents, other than
exhibits to these documents, which we will send to you for a reasonable fee.
Requests should be directed to the Office of the Secretary, PSINet Inc., 44983
Knoll Square, Ashburn, Virginia 20147 (telephone (703) 726-4100).

                      DISCLOSURE OF COMMISSION POSITION ON
                 INDEMNIFICATION FOR SECURITIES ACT LIABILITIES

         Insofar as indemnification for liabilities arising under the Securities
Act of 1933 may be permitted to directors, officers, and controlling persons of
PSINet pursuant to the foregoing provisions, PSINet has been informed that in
the opinion of the Securities and Exchange Commission such indemnification is
against public policy as expressed in the Securities Act of 1933 and is,
therefore, unenforceable. In the event that a claim for indemnification against
such liabilities (other than the payment by registrant of expenses incurred 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, 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 of 1933 and will be governed by the
final adjudication of such issue.

         Except to the extent set forth herein, there is no charter provision,
by-law, contract, arrangement or statute pursuant to which any director or
officer of registrant is indemnified in any manner against any liability which
he may incur in his capacity as such.

                                      -9-
SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this registration
statement to be signed on its behalf by the undersigned, thereunto duly
authorized in the City of Ashburn, Commonwealth of Virginia on June 15, 2000.

                           PSINET INC.

                           By: /s/ William L. Schrader
                             -------------------------------
                             William L. Schrader, Chairman
                             and Chief Executive Officer

                                POWER OF ATTORNEY

         KNOW ALL MEN BY THESE PRESENTS, that each person whose signature
appears below hereby constitutes and appoints William L. Schrader, Harold S.
Wills, David N. Kunkel and Kathleen B. Horne, and each or any of them, his true
and lawful attorney-in-fact and agent, with full power of substitution and
resubstitution, for him and in his name, place and stead, in any and all
capacities, to sign any registration statement filed pursuant to Rule 462(b)
under the Securities Act of 1933 and any and all amendments (including
post-effective amendments) to this registration statement and to any
registration statement filed pursuant to Rule 462(b), and to file same, with all
exhibits thereto and other documents in connection therewith, with the
Securities and Exchange Commission, granting unto each said attorney-in-fact and
agent full power and authority to do and perform each and every act and thing
requisite and necessary to be done in and about the foregoing, as fully to all
intents and purposes as he might or could do in person, hereby ratifying and
confirming all that said attorney-in-fact and agent or either of them, or their
or his substitute or substitutes, may lawfully do or cause to be done by virtue
hereof.

         Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the dates indicated.

       Name                            Title                          Date
       -----                           -----                         ------

/s/ William L. Schrader        Chairman, Chief Executive
------------------------      Officer and Director (Principal     June 15, 2000
William L. Schrader               Executive Officer)

/s/ Harold S. Wills            President, Chief Operating         June 15, 2000
------------------------          Officer and Director
Harold S. Wills

/s/ David N. Kunkel                 Vice Chairman,
------------------------        Executive Vice President          June 15, 2000
David N. Kunkel                      and Director

                                      -10-
/s/ Jorge R. Forgues          Vice President and Acting Chief
------------------------             Financial Officer            June 15, 2000
Jorge R. Forgues                    (Principal Financial
                                  and Accounting Officer)

/s/ William H. Baumer                    Director                 June 15, 2000
------------------------
William H. Baumer

------------------------                 Director                 June __, 2000
Ralph J. Swett

                                         Director                 June __, 2000
------------------------
Ian P. Sharp

                                      -11-
EXHIBIT INDEX

Exhibit
 No.      Description                             Location
-------   ------------                            ---------

4.1      Executive Stock Incentive Plan,        Incorporated by reference to
         as amended                             Exhibit B to PSINet's Proxy
                                                Statement on Schedule 14A filed
                                                with the Securities and Exchange
                                                Commission on April 7, 2000
                                                (File No.0-25812)

4.2      Strategic Stock Incentive Plan,        Incorporated by reference to
         as amended                             Exhibit B to PSINet's Proxy
                                                Statement on Schedule 14A filed
                                                with the Securities and Exchange
                                                Commission on April 7, 2000
                                                (File No.0-25812)

5.1      Opinion of Nixon Peabody LLP           Filed herewith

23.1     Consent of Nixon Peabody LLP           Contained in opinion filed as
                                                Exhibit 5.1 to this Registration
                                                Statement

23.2     Consent of PricewaterhouseCoopers LLP  Filed herewith

                                      -12-