<PAGE>

                   As filed with the Securities and Exchange
                        Commission on November 28, 2000.


               UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549

                                   FORM S-8

            REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                    DIAMOND TECHNOLOGY PARTNERS INCORPORATED
             (Exact name of registrant as specified in its charter)

               DELAWARE                                36-4069408
    (State or other jurisdiction of        (IRS Employer Identification No.)
    incorporation or organization)

                       875 N. Michigan Avenue, Suite 3000
                            Chicago, Illinois 60611
                                 (312) 255-5000
    (Address, including ZIP code, and telephone number, including area code,
                  of registrant's principal executive offices)

                DIAMOND TECHNOLOGY PARTNERS INCORPORATED AMENDED
                    AND RESTATED 1998 EQUITY INCENTIVE PLAN
                              (Full title of plan)

              Nancy K. Bellis, Vice President and General Counsel
                    Diamond Technology Partners Incorporated
                       875 N. Michigan Avenue, Suite 3000
                            Chicago, Illinois 60611
                                 (312) 255-5000
 (Name, address, including ZIP code, and telephone number, including area code,
                             of agent for service)

                        CALCULATION OF REGISTRATION FEE
<TABLE>
<CAPTION>

Title of Securities to     Amount to be      Proposed Maximum      Proposed Maximum        Amount
be Registered)             Registered(1)    Offering Price per    Aggregate Offering    of Registra-
                                                 Share(1)               Price             tion Fee
<S>                        <C>              <C>                   <C>                   <C>

Class B Common Stock         7,750,000            $30.34             $235,135,000         $62,100
par value $.001 per
share

Class A Common Stock                  (2)                     (2)
par value $.001 per
share
</TABLE>

----------------
1.   Computed in accordance with Rule 457(h) under the Securities Act of 1933
     solely for the purpose of calculating the registration fee. Computation
     based upon the average of the high and low prices of the Class A Common
     Stock of the Registrant as reported on the Nasdaq National Market as of
     closing on November 22, 2000.

2.   This Registration Statement also covers the Shares of Class A Common Stock,
     par value $.001 per share, into which Class B Common Stock may be converted
     and that they may be issued in lieu of the Class B Common Stock to
     optionees who have ceased to be employees of the Registrant.

<PAGE>

Item 3. Incorporation of Certain Documents by Reference

     The following documents that have been filed with the Securities and
Exchange Commission (the "Commission") by Diamond Technology Partners
Incorporated (the "Company") are incorporated herein by reference:

     (a)  The Company's Registration Statement on Form S-8 filed on November 24,
1998 (File No. 333-67899);

     (b)  The Company's Annual Report on Form 10-K for the fiscal year ended
March 31, 2000 (File No. 000-22125), containing audited financial statements for
the Company's latest fiscal year;

     (c)  All other reports filed pursuant to Section 13(a) or 15(d) of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), (File No.
000-22125) since the end of the fiscal year covered by the Annual Report on Form
10-K referenced above; and

     (d)  The description of the Class A Common Stock which is contained in the
registration statement on Form 8-A filed with the Commission (File No.
000-22125) under the Exchange Act, including any subsequent amendment or any
report filed for the purpose of updating such description.

     All documents filed by the Company pursuant to Sections 13(a), 13(c), 14 or
15(d) of the Exchange Act after 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
then remaining unsold are deemed to be incorporated by reference into this
Registration Statement and to be a part hereof from the respective dates of
filing of such documents (such documents, and the documents enumerated above,
being hereinafter referred to as "Incorporated Documents").

     Any statement contained in an Incorporated Document 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
Incorporated Document modifies or supersedes such statement. Any such statement
so modified or superseded shall not be deemed, except as so modified or
superseded, to constitute a part of this Registration Statement.

Item 8. Exhibits

Exhibit Number      Description of Exhibit

4.1                 Restated Certificate of Incorporation of the Company filed
                    as Exhibit 3.1 to the Company's Registration Statement on
                    Form S-1 (filed with the Commission on February 21, 1997,
                    (File No. 333-17785) (the "Form S-1"), and hereby
                    incorporated by reference).

4.2                 Form of Amendment to the Restated Certificate of
                    Incorporation of the Company (filed with the Commission on
                    November 6, 2000, (File No. 333-47830) and hereby
                    incorporated by reference).

4.3                 Amended and Restated By-laws of the Company (filed as
                    Exhibit 3.2 to the Form S-1 and hereby incorporated by
                    reference).

4.4                 Diamond Technology Partners Incorporated Amended and
                    Restated 1998 Equity Incentive Plan.

4.5                 Form of Stock Option Agreement for Non-Partners.

4.6                 Form of Stock Option Agreement for Partners.

5.1                 Opinion of the Company's Vice President and General Counsel
                    as to the legality of the securities being registered.

23.1                Consent of the Company's Vice President and General Counsel
                    (included in her opinion filed as Exhibit 5.1).

23.2                Consent of KPMG LLP.

                                       2
<PAGE>

                                  SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, as amended, 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 Chicago, State of Illinois, on this 28th day of
November, 2000.

                                   DIAMOND TECHNOLOGY PARTNERS INCORPORATED

                                   By: /S/ Melvyn E. Bergstein
                                       -----------------------
                                   Melvyn E. Bergstein, Chairman and Chief
                                   Executive Officer

     Pursuant to the requirements of the Securities Act of 1933, as amended, the
Management Committee of Diamond Technology Partners Incorporated (which
administers the employee benefit plan) has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereto duly authorized
in the City of Chicago, State of Illinois on the 28th day of November, 2000.

                                   Diamond Technology Partners Incorporated
                                   Amended and Restated 1998 Equity Incentive
                                   Plan

                                   By: /S/ Melvyn E. Bergstein
                                       -----------------------
                                        Melvyn E. Bergstein
                                        Management Committee Chairman

                               POWER OF ATTORNEY

     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Melvyn E. Bergstein and Michael E.
Mikolajczyk, and each of them, his true and lawful attorneys-in-fact and agents,
with full power of substitution, for him and in 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 file the same, with all
exhibits thereto and all documents in connection therewith, with the Securities
and Exchange Commission, granting unto said attorneys-in-fact and agents 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 each said attorneys-in fact and agents, 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 of 1933, this Registration
Statement has been signed by the following persons in the capacities indicated
on the 28/th/ day of November, 2000.

           Signature                              Title

/s/ Melvyn E. Bergstein         Chairman and Chief Executive Officer (Principal
----------------------------
Melvyn E. Bergstein             Executive Officer)

/s/ Karl E. Bupp                Chief Financial Officer and Treasurer (Principal
----------------------------
Karl E. Bupp                    Financial and Accounting Officer)

/s/ Michael E. Mikolajczyk      Vice Chairman, Secretary and Director
----------------------------
Michael E. Mikolajczyk


/s/ Adam J. Gutstein            President and Director
----------------------------
Adam J. Gutstein

/s/ John J. Sviokla             Vice Chairman and Director
----------------------------
John J. Sviokla

/s/ Edward R. Andersen          Director
----------------------------
Edward R. Andersen

/s/ Donald R. Caldwell          Director
----------------------------
Donald R. Caldwell

/s/ Mark L. Gordon              Director
----------------------------
Mark L. Gordon

/s/ Alan C. Kay                 Director
----------------------------
Alan C. Kay

/s/ John D. Loewenberg          Director
----------------------------
John D. Loewenberg

/s/ Christopher J. Moffit       Director
----------------------------
Christopher J. Moffit

/s/ Arnold R. Weber             Director
----------------------------
Arnold R. Weber

                                       3
<PAGE>

            INDEX TO EXHIBITS TO REGISTRATION STATEMENT ON FORM S-8

Exhibit Number      Description of Document                                Page

4.1                 Restated Certificate of Incorporation of the Company
                    filed as Exhibit 3.1 to the Company's Registration
                    Statement on Form S-1 and any amendments thereto
                    (filed with the Commission on February 21, 1997,
                    (File No. 333-17785) (the "Form S-1"), and hereby
                    incorporated by reference).

4.2                 Form of Amendment to the Restated Certificate of
                    Incorporation of the Company (filed with the
                    Commission on November 6, 2000, (File No. 333-47830)
                    and hereby incorporated by reference).

4.3                 Amended and Restated By-laws of the Company (filed
                    as Exhibit 3.2 to the Form S-1 and hereby
                    incorporated by reference).

4.4                 Diamond Technology Partners Incorporated Amended and
                    Restated 1998 Equity Incentive Plan.

4.5                 Form of Stock Option Agreement for Non-Partners.

4.6                 Form of Stock Option Agreement for Partners.

5.1                 Opinion of the Company's Vice President and General
                    Counsel as to the legality of the securities being
                    registered.

23.1                Consent of the Company's Vice President and General
                    Counsel (included in her opinion filed as Exhibit
                    5.1).

23.2                Consent of KPMG LLP.

                                       4
[{"type": "S-8", "sequence": "1", "filename": "0001.txt", "description": "FORM S-8", "secsgml_size_bytes": 12573}]
{"company-data": {"conformed-name": "DIAMOND TECHNOLOGY PARTNERS INC", "cik": "0000924940", "assigned-sic": "8742", "irs-number": "364069408", "state-of-incorporation": "DE", "fiscal-year-end": "0331"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-50834", "film-number": "778237"}, "business-address": {"street1": "875 NORTH MICHIGAN AVE SUITE 3000", "city": "CHICAGO", "state": "IL", "zip": "60611", "phone": "3122555000"}, "mail-address": {"street1": "875 NORTH MICHIGAN AVE STE 3000", "city": "CHICAGO", "state": "IL", "zip": "60611"}}
As filed with the Securities and Exchange
                        Commission on November 28, 2000.

               UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549

                                   FORM S-8

            REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                    DIAMOND TECHNOLOGY PARTNERS INCORPORATED
             (Exact name of registrant as specified in its charter)

               DELAWARE                                36-4069408
    (State or other jurisdiction of        (IRS Employer Identification No.)
    incorporation or organization)

                       875 N. Michigan Avenue, Suite 3000
                            Chicago, Illinois 60611
                                 (312) 255-5000
    (Address, including ZIP code, and telephone number, including area code,
                  of registrant's principal executive offices)

                DIAMOND TECHNOLOGY PARTNERS INCORPORATED AMENDED
                    AND RESTATED 1998 EQUITY INCENTIVE PLAN
                              (Full title of plan)

              Nancy K. Bellis, Vice President and General Counsel
                    Diamond Technology Partners Incorporated
                       875 N. Michigan Avenue, Suite 3000
                            Chicago, Illinois 60611
                                 (312) 255-5000
 (Name, address, including ZIP code, and telephone number, including area code,
                             of agent for service)

                        CALCULATION OF REGISTRATION FEE
Title of Securities to     Amount to be      Proposed Maximum      Proposed Maximum        Amount
be Registered)             Registered(1)    Offering Price per    Aggregate Offering    of Registra-
                                                 Share(1)               Price             tion Fee
Class B Common Stock         7,750,000            $30.34             $235,135,000         $62,100
par value $.001 per
share

Class A Common Stock                  (2)                     (2)
par value $.001 per
share
----------------
1.   Computed in accordance with Rule 457(h) under the Securities Act of 1933
     solely for the purpose of calculating the registration fee. Computation
     based upon the average of the high and low prices of the Class A Common
     Stock of the Registrant as reported on the Nasdaq National Market as of
     closing on November 22, 2000.

2.   This Registration Statement also covers the Shares of Class A Common Stock,
     par value $.001 per share, into which Class B Common Stock may be converted
     and that they may be issued in lieu of the Class B Common Stock to
     optionees who have ceased to be employees of the Registrant.
Item 3. Incorporation of Certain Documents by Reference

     The following documents that have been filed with the Securities and
Exchange Commission (the "Commission") by Diamond Technology Partners
Incorporated (the "Company") are incorporated herein by reference:

     (a)  The Company's Registration Statement on Form S-8 filed on November 24,
1998 (File No. 333-67899);

     (b)  The Company's Annual Report on Form 10-K for the fiscal year ended
March 31, 2000 (File No. 000-22125), containing audited financial statements for
the Company's latest fiscal year;

     (c)  All other reports filed pursuant to Section 13(a) or 15(d) of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), (File No.
000-22125) since the end of the fiscal year covered by the Annual Report on Form
10-K referenced above; and

     (d)  The description of the Class A Common Stock which is contained in the
registration statement on Form 8-A filed with the Commission (File No.
000-22125) under the Exchange Act, including any subsequent amendment or any
report filed for the purpose of updating such description.

     All documents filed by the Company pursuant to Sections 13(a), 13(c), 14 or
15(d) of the Exchange Act after 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
then remaining unsold are deemed to be incorporated by reference into this
Registration Statement and to be a part hereof from the respective dates of
filing of such documents (such documents, and the documents enumerated above,
being hereinafter referred to as "Incorporated Documents").

     Any statement contained in an Incorporated Document 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
Incorporated Document modifies or supersedes such statement. Any such statement
so modified or superseded shall not be deemed, except as so modified or
superseded, to constitute a part of this Registration Statement.

Item 8. Exhibits

Exhibit Number      Description of Exhibit

4.1                 Restated Certificate of Incorporation of the Company filed
                    as Exhibit 3.1 to the Company's Registration Statement on
                    Form S-1 (filed with the Commission on February 21, 1997,
                    (File No. 333-17785) (the "Form S-1"), and hereby
                    incorporated by reference).

4.2                 Form of Amendment to the Restated Certificate of
                    Incorporation of the Company (filed with the Commission on
                    November 6, 2000, (File No. 333-47830) and hereby
                    incorporated by reference).

4.3                 Amended and Restated By-laws of the Company (filed as
                    Exhibit 3.2 to the Form S-1 and hereby incorporated by
                    reference).

4.4                 Diamond Technology Partners Incorporated Amended and
                    Restated 1998 Equity Incentive Plan.

4.5                 Form of Stock Option Agreement for Non-Partners.

4.6                 Form of Stock Option Agreement for Partners.

5.1                 Opinion of the Company's Vice President and General Counsel
                    as to the legality of the securities being registered.

23.1                Consent of the Company's Vice President and General Counsel
                    (included in her opinion filed as Exhibit 5.1).

23.2                Consent of KPMG LLP.

                                       2
SIGNATURES

     Pursuant to the requirements of the Securities Act of 1933, as amended, 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 Chicago, State of Illinois, on this 28th day of
November, 2000.

                                   DIAMOND TECHNOLOGY PARTNERS INCORPORATED

                                   By: /S/ Melvyn E. Bergstein
                                       -----------------------
                                   Melvyn E. Bergstein, Chairman and Chief
                                   Executive Officer

     Pursuant to the requirements of the Securities Act of 1933, as amended, the
Management Committee of Diamond Technology Partners Incorporated (which
administers the employee benefit plan) has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereto duly authorized
in the City of Chicago, State of Illinois on the 28th day of November, 2000.

                                   Diamond Technology Partners Incorporated
                                   Amended and Restated 1998 Equity Incentive
                                   Plan

                                   By: /S/ Melvyn E. Bergstein
                                       -----------------------
                                        Melvyn E. Bergstein
                                        Management Committee Chairman

                               POWER OF ATTORNEY

     KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Melvyn E. Bergstein and Michael E.
Mikolajczyk, and each of them, his true and lawful attorneys-in-fact and agents,
with full power of substitution, for him and in 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 file the same, with all
exhibits thereto and all documents in connection therewith, with the Securities
and Exchange Commission, granting unto said attorneys-in-fact and agents 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 each said attorneys-in fact and agents, 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 of 1933, this Registration
Statement has been signed by the following persons in the capacities indicated
on the 28/th/ day of November, 2000.

           Signature                              Title

/s/ Melvyn E. Bergstein         Chairman and Chief Executive Officer (Principal
----------------------------
Melvyn E. Bergstein             Executive Officer)

/s/ Karl E. Bupp                Chief Financial Officer and Treasurer (Principal
----------------------------
Karl E. Bupp                    Financial and Accounting Officer)

/s/ Michael E. Mikolajczyk      Vice Chairman, Secretary and Director
----------------------------
Michael E. Mikolajczyk

/s/ Adam J. Gutstein            President and Director
----------------------------
Adam J. Gutstein

/s/ John J. Sviokla             Vice Chairman and Director
----------------------------
John J. Sviokla

/s/ Edward R. Andersen          Director
----------------------------
Edward R. Andersen

/s/ Donald R. Caldwell          Director
----------------------------
Donald R. Caldwell

/s/ Mark L. Gordon              Director
----------------------------
Mark L. Gordon

/s/ Alan C. Kay                 Director
----------------------------
Alan C. Kay

/s/ John D. Loewenberg          Director
----------------------------
John D. Loewenberg

/s/ Christopher J. Moffit       Director
----------------------------
Christopher J. Moffit

/s/ Arnold R. Weber             Director
----------------------------
Arnold R. Weber

                                       3
INDEX TO EXHIBITS TO REGISTRATION STATEMENT ON FORM S-8

Exhibit Number      Description of Document                                Page

4.1                 Restated Certificate of Incorporation of the Company
                    filed as Exhibit 3.1 to the Company's Registration
                    Statement on Form S-1 and any amendments thereto
                    (filed with the Commission on February 21, 1997,
                    (File No. 333-17785) (the "Form S-1"), and hereby
                    incorporated by reference).

4.2                 Form of Amendment to the Restated Certificate of
                    Incorporation of the Company (filed with the
                    Commission on November 6, 2000, (File No. 333-47830)
                    and hereby incorporated by reference).

4.3                 Amended and Restated By-laws of the Company (filed
                    as Exhibit 3.2 to the Form S-1 and hereby
                    incorporated by reference).

4.4                 Diamond Technology Partners Incorporated Amended and
                    Restated 1998 Equity Incentive Plan.

4.5                 Form of Stock Option Agreement for Non-Partners.

4.6                 Form of Stock Option Agreement for Partners.

5.1                 Opinion of the Company's Vice President and General
                    Counsel as to the legality of the securities being
                    registered.

23.1                Consent of the Company's Vice President and General
                    Counsel (included in her opinion filed as Exhibit
                    5.1).

23.2                Consent of KPMG LLP.

                                       4