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                                                                     EXHIBIT 2.2

                                                                  EXECUTION COPY

                   AMENDMENT NO. 1 TO STOCK PURCHASE AGREEMENT

         THIS AMENDMENT NO. 1, dated as of February 29, 2000 (this "Amendment"),
to the STOCK PURCHASE AGREEMENT, dated as of January 11, 2000 (the "AGREEMENT"),
between STRATEGIC DISTRIBUTION, INC., a Delaware corporation ("SELLER"), and
PROJECT SOFTWARE & DEVELOPMENT, INC., a Massachusetts corporation ("PURCHASER").

                              PRELIMINARY STATEMENT

         WHEREAS, the parties hereto have executed and delivered the Agreement
and have agreed to amend the Agreement as set forth in this Amendment.

         NOW, THEREFORE, for good and valuable consideration, the sufficiency
and receipt of which are hereby acknowledged, the parties hereto agree as
follows:

                  SECTION 1. CERTAIN DEFINITIONS. Capitalized terms used but not
defined in this Amendment shall have the meanings given to such terms in the
Agreement.

                  SECTION 2. DELETION OF CERTAIN DEFINITIONS. The defined terms
"Escrow Agreement" and "Indemnification Agreement" shall be deleted from Section
1.1 of the Agreement and all references to such agreements in the Agreement
shall be deleted therefrom.

                  SECTION 3. PURCHASE AND SALE OF SHARES. Subsection 2.2(b) of
the Agreement is amended by replacing such subsection in its entirety with the
following:

                  "(b) Purchaser will deliver, or cause to be delivered, by wire
transfer of immediately available funds in an aggregate amount equal to
$55,000,000 (the 'PURCHASE PRICE') to such account as Seller shall designate
prior to the Closing Date."

                  SECTION 4. CONDITIONS TO SELLER'S OBLIGATIONS. Section 7.9 of
the Agreement is hereby deleted in its entirety.

                  SECTION 5. CONDITIONS TO PURCHASER'S OBLIGATIONS. Section 8.9
and Section 8.10 of the Agreement are hereby deleted in their entirety.



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                  SECTION 6. INDEMNIFICATION; CERTAIN LIMITATIONS. The last
proviso of subsection 10.2(a) of the Agreement is hereby deleted in its
entirety.

                  SECTION 7. LETTER OF CREDIT OBLIGATIONS. Seller shall
indemnify Purchaser for any payment made under the letters of credit referenced
in Schedule 3.4 of the Agreement to the extent that such payment relates to work
performed by the Company prior to the Closing Date. Purchaser shall indemnify
Seller for any payment made under the letters of credit referenced in Schedule
3.4 of the Agreement to the extent that such payment relates to work performed
by the Company on or after the Closing Date.

                  SECTION 8. DESCRIPTIVE HEADINGS. The descriptive headings of
the several sections of this Amendment are inserted for convenience only and
shall not control or affect the meaning or construction of any of the provisions
hereof.

                  SECTION 9. COUNTERPARTS. For the convenience of the parties,
any number of counterparts of this Amendment may be executed by any one or more
parties hereto, and each such executed counterpart shall be, and shall be deemed
to be, an original, but all of which shall constitute, and shall be deemed to
constitute, in the aggregate but one and the same instrument.

                  SECTION 10. GOVERNING LAW. This Amendment and the legal
relations between the parties hereto shall be governed by and construed in
accordance with the laws of the State of Delaware, applicable to contracts made
and to be performed within such State. Any legal action or other proceeding for
any purpose with respect to this Amendment shall be brought in the state or
federal courts in the State of Delaware. The parties hereby submit to the
exclusive jurisdiction of such courts and waive any objection.

                  SECTION 11. SUCCESSORS AND ASSIGNS. This Amendment shall be
binding upon the parties hereto and their respective successors and legal
assigns and shall inure to the benefit of the parties hereto and, except as
otherwise provided herein, their respective successors and legal assigns. No
person other than the parties hereto and their respective successors and legal
assigns shall have any rights or claims under this Amendment.


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                  IN WITNESS WHEREOF, Seller and Purchaser have executed and
delivered this Amendment as of the day and year first written above.

                                           STRATEGIC DISTRIBUTION, INC.


                                           By:
                                              ----------------------------------
                                              Name:
                                              Title:


                                           PROJECT SOFTWARE & DEVELOPMENT, INC.


                                           By: /s/ Norman E. Drapeau, Jr.
                                              ----------------------------------
                                              Name:
                                              Title:







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                  IN WITNESS WHEREOF, Seller and Purchaser have executed and
delivered this Amendment as of the day and year first written above.

                                           STRATEGIC DISTRIBUTION, INC.


                                           By: /s/ John M. Sergey
                                              ----------------------------------
                                              Name:  John M. Sergey
                                              Title: President


                                           PROJECT SOFTWARE & DEVELOPMENT, INC.


                                           By:
                                              ----------------------------------
                                              Name:
                                              Title:




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