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                                                                    Exhibit 10.1



               PROJECT SOFTWARE & DEVELOPMENT, INC. & SUBSIDIARIES

                          YEAR ENDED SEPTEMBER 30, 2000

                              EXECUTIVE BONUS PLAN




                                 April 13, 2000


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                      PROJECT SOFTWARE & DEVELOPMENT, INC.
                          YEAR ENDED SEPTEMBER 30, 2000
                              EXECUTIVE BONUS PLAN


1.   PURPOSE
     -------

     The purpose of the FY2000 Executive Bonus Plan ("Plan") is to provide key
     management employees of Project Software & Development, Inc. with an
     incentive to make significant and extraordinary contributions to the
     long-term performance and growth of the Company, to join the common
     interest of the Company and key executives, and to attract and retain
     executives of exceptional ability.

2.   ADMINISTRATION
     --------------

     2.1  The Plan shall be administered by the Compensation Committee of the
          Board of Directors of the Company (the "Committee"). The Committee
          will base all decisions and awards on quarterly and annual financial
          statements filed with the Securities and Exchange Commission.

     2.2  By adoption of this Plan the Board has deemed eligible those
          individuals named in Appendix I. The Board shall have full and
          complete authority and discretion to make binding decisions on the
          administration of the Plan and shall adopt such rules and regulations
          and make all other determinations deemed by it necessary or desirable
          for the administration of the Plan.

     2.3  The Compensation Committee and Board of Directors of the Company shall
          have the authority to amend or terminate the Plan, provided, however,
          that if the Plan is amended or terminated, the Company shall be
          required to complete payment to each Participant of the amount which
          that Participant otherwise would have received based on the provisions
          set forth in paragraph 7.2.

3.   DEFINITIONS
     -----------

     3.1  PLAN YEAR means the fiscal year ended September 30, 2000.

     3.2  PLAN QUARTER means each of the three-month periods ended December 31,
          1999, March 31, 2000, June 30, 2000, and September 30, 2000.

     3.3  PARTICIPANT means any executive of the Company who is designated in
          Appendix I.

     3.4  PERMANENT DISABILITY, means a Participant's inability, as a result of
          illness, incapacity, disease or calamity to perform a substantial part
          of his primary job responsibilities as set forth in his employment
          contract or job description for any concurrent six month period.


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     3.5  PLAN means this FY2000 Executive Bonus Plan.

     3.6  Except as otherwise indicated by the context, any masculine term used
          herein also shall include the feminine; the plural shall include the
          singular and the singular shall include the plural.

     3.7  COMPANY means Project Software & Development, Inc. and its
          subsidiaries included in the consolidated financial statements.

     3.8  PLAN NET INCOME means net income as disclosed in the consolidated
          quarterly financial statements of the Company, before deductions and
          additions of:

          (i)   Taxes calculated by net income.
          (ii)  Extraordinary items as defined under US generally accepted
                accounting principles.
          (iii) One time expense adjustments arising out of any acquisition
                accounted for as either a pooling or purchase.
          (iv)  Goodwill/purchased intangible assets arising out of
                acquisitions.

     3.9  PLAN REVENUE means total revenues as disclosed in the consolidated
          quarterly financial statements of the Company.


4.   ELIGIBILITY AND PARTICIPATION
     -----------------------------

     Executives eligible for bonuses under the Plan shall be those individuals
     specified in Appendix I.

5.   BONUS FUNDING MECHANISM
     -----------------------

     5.1  The on-target bonus Fund will be determined as follows:

          (a)  Each Participant will be eligible to receive up to 60% of
               on-target funded bonus if the Company achieves quarterly and
               annual Plan Revenues and Net Income as stated in Appendix II.

          (b)  The percentage of the on-target bonus described in Appendix I
               earned by each Participant on achievement of the amounts stated
               in Appendix II in respect of each quarter and year end is:

               (i)   Q1        5% based on revenue,  5% based on earnings

               (ii)  Q2        5% based on revenue,  5% based on earnings

               (iii) Q3        5% based on revenue,  5% based on earnings

               (iv)  Q4        5% based on revenue,  5% based on earnings

               (v)   Year end 10% based on revenue, 10% based on earnings


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          (c)  In the event that the achievement in any quarter or for the year
               is less than the amounts stated in Appendix II, but is equal to
               or greater than 90% of the amount in question, then a partial
               bonus shall be paid to each participant. The partial bonus shall
               be equal to the actual achievement divided by the amount stated
               in Appendix II times the on-target bonus the participant would
               otherwise have earned.

          (d)  In the event that the achievement in any quarter or for the year
               is greater than the amounts stated in Appendix II, than an
               incremental bonus shall be paid to each participant. The
               incremental bonus shall be equal to the actual achievement
               divided by the amount stated in Appendix II times the on-target
               bonus the participant would otherwise have earned, except that
               the incremental bonus in each instance shall not be greater than
               110% of the on-target bonus the participant would have received
               in respect of the individual quarterly or annual earnings or
               revenue based component.

          (e)  20% of the on-target bonus described in Appendix I earned by each
               participant shall be based on share price appreciation. The
               calculation for this portion of the year end bonus shall be as
               follows: an amount equal to .20% of the on-target year end bonus
               shall be earned by each participant for each 1% increase in the
               share price over the term of fiscal 2000, adjusted for any future
               stock splits, over $26.75 (the share price as of the close on the
               last day of the previous fiscal year adjusted for the stock split
               in December, 1999). By way of example, if the share price closes
               at $53.50 on September 30, 2000, (a 100% increase) each
               participant would earn 100 times .20 or 20% of the specified
               on-target bonus as set forth in Appendix I on account of share
               price appreciation. In no event shall the amount earned by each
               participant on account of share price appreciation be greater
               than 20% of on-target bonus. In the event an individual is not
               employed at the beginning of a fiscal year, their first day of
               employment shall be used as the starting share price for the
               purpose of calculating share price appreciation during the
               balance of the fiscal year and the maximum 20% of on-target award
               shall be prorated to an amount proportional to the number of days
               remaining in the fiscal year.

          (f)  20% of the on-target year end bonus shall be at the discretion of
               the Compensation Committee in the case of the Chairman and the
               CEO and in the case of the participants in Appendix I, Section
               II, based upon an evaluation of the individual goals agreed to
               between the CEO and the participant as evaluated by the CEO and
               the Chairman.

6.   PAYMENT OF BONUSES
     ------------------

     Funded bonus will be payable not later than sixty days after the end of the
     period in which the bonus was earned provided that the results for the
     period have been issued to the public.


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7.   TERMINATION OF EMPLOYEE
     -----------------------

     7.1  If a Participant's employment is terminated prior to the conclusion of
          any Plan Quarter or, following the conclusion of a Plan Year, or prior
          to any payment being made:

          (a)  By reason of (i) any deliberate material breach by the
               Participant of his employment obligations with the Company,
               which, if curable, is not cured within ten (10) days after the
               Company shall have notified the Participant in writing describing
               to Participant all material facts concerning such breach, (ii)
               any deliberate material breach by the Participant of his
               employment obligations with the Company, which is not curable
               according to notice from the Company, or (iii) the conviction of
               a felony or the commission of a material, fraudulent act by the
               Participant against the Company;

          (b)  Voluntarily by Participant other than for a "Reason Constituting
               Good Cause." Reasons Constituting Good Cause are limited to: (i)
               a significant change in the nature and scope of Participant's
               duties combined with a change in the Participant's title
               resulting in a position of materially lesser authority, or (ii) a
               reduction in the Participant's base compensation.

          Then, Participant shall cease to have any rights to any amounts unpaid
          on the date of termination of employment.

     7.2  If a Participant's employment is terminated:

          (a)  By reason of Death, Permanent Disability; or

          (b)  By the Company for a reason other than one described at
               subparagraph 7.1(a);

          If such a termination occurs prior to the conclusion of any Plan
          Quarter or Year, the Participant shall receive the amount which the
          Participant otherwise would have been entitled to receive had he
          remained in the employ of the Company through the end of the Plan
          Year, but pro-rated based on the number of complete months of
          employment with the Company during such Plan Year. The amount earned
          shall be paid according to the Plan rules.


8.   BENEFICIARY DESIGNATIONS
     ------------------------

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     8.1  If a Participant's employment with the Company is terminated by his
          death or if he dies after termination of his employment but prior to
          the distribution to him of all amounts payable to him under the Plan,
          any amounts otherwise payable to him hereunder shall be distributed to
          his designated beneficiary or beneficiaries. For the purposes of this
          plan a Participant's beneficiary will be the beneficiary designated
          under Company provided life insurance coverage. However, a Participant
          may from time to time revoke or change any beneficiary designation on
          file with the Company.

          If there is no effective beneficiary designation on file with the
          Company at the time of a Participant's death, distribution of amounts
          otherwise payable to the deceased Participant under this Plan shall be
          made to the Participant's estate. If a beneficiary designated by the
          Participant to receive his benefits shall survive the Participant but
          die before receiving all distributions hereunder, the balance thereof
          shall be paid to such deceased beneficiary's estate, unless the
          deceased beneficiary designation provides otherwise.

     8.2  The Company shall deduct from the distributions to be made to a
          Participant or his designated beneficiary or beneficiaries under this
          Plan any federal, state or local withholding or other taxes or charges
          which the Company is from time to time required to deduct under
          applicable law and all amounts distributable under this Plan are
          stated herein before any such deductions. The Company may rely on a
          written opinion from its legal counsel regarding any questions which
          may arise in connection with any such deductions.

9.   RIGHTS, PRIVILEGES AND DUTIES OF PARTICIPATION
     ----------------------------------------------

     9.1  No participant or other person shall have any interest in any fund or
          in any specific asset or assets of the Company and its Subsidiaries by
          reason of being a Participant under this Plan nor any right to receive
          any distributions under the Plan except as and to the extent expressly
          provided in the Plan.

     9.2  The Company shall have the right, but shall be under no obligation, to
          segregate cash to fund bonuses payable under the Plan. However, any
          such segregated amounts shall at all times remain Company assets,
          subject to the claims of its creditors.

     9.3  Each Participant shall be entitled to receive a current copy of the
          Plan upon his designation as a Participant if a written request for a
          copy of the Plan is provided to the Chief Executive Officer or the
          Chairman of the Board. Thereafter, as long as he remains a
          Participant, he shall be entitled to receive copies of any amendments
          to the Plan within sixty (60) days after their adoption.

     9.4  The designation of any employee as a Participant under this Plan shall
          not be construed as conferring upon such employee any right to remain
          in the employ of the Company and each such Participant shall remain an
          employee at will. The right of


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          the Company to discipline or discharge an employee shall not be
          affected in any manner by reason of such employee's designation as a
          Participant under this Plan.

     9.5  To the extent permitted by law, the right of any Participant or any
          beneficiary to receive any payment hereunder shall not be subject to
          alienation, transfer, sale, assignment, pledge, attachment,
          garnishment or encumbrance of any kind. Any attempt to alienate,
          transfer, sell, assign, pledge or otherwise encumber any such payment
          whether presently or thereafter payable, shall be void. Any payment
          due hereunder shall not in any manner be subject to any debts or
          liabilities of any Participant or his beneficiary.


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                                   APPENDIX I


                      PROJECT SOFTWARE & DEVELOPMENT, INC.

                              EXECUTIVE BONUS PLAN

                              ELIGIBLE PARTICIPANTS



<TABLE>
<CAPTION>
                                                      ON-TARGET BONUS
                                                         AS A % OF         ON-TARGET
                                   BASE SALARY          BASE SALARY          BONUS
                                   -----------        ---------------      ---------

<S>                                <C>                <C>                  <C>
     SECTION I:

          CHIP DRAPEAU               325,000                125%             406,250

          ROBERT DANIELS             325,000                125%             406,250


     SECTION II:

          CFO(ESTIMATE)              200,000                100%             200,000

          BILL SAWYER                200,000                100%             200,000

          JACK YOUNG                 200,000                100%             200,000

          TED WILLIAMS               200,000                100%             200,000
</TABLE>

     Footnotes:

     -    Salaries to be effective January 1, 2000.

     -    Mr. Williams bonus will be offset by any prior payments made under his
          personal compensation plan, as he is being transitioned into this Plan
          in Q2. Mr. Williams will be entitled to an incremental year end bonus
          equal to .2% of the amount by which worldwide software revenues exceed
          $85,000,000.

     -    The CFO's on-target bonus will be calculated on a prorated basis
          commencing on the start date of the CFO.


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                                   APPENDIX II


                      PROJECT SOFTWARE & DEVELOPMENT, INC.

                              EXECUTIVE BONUS PLAN

                          ON-TARGET REVENUE & EARNINGS



<TABLE>
<CAPTION>
                       TARGET           FY1999            FY2000             FY2000
                     YR OVER YR         ACTUAL           ON-TARGET          ON-TARGET
                    REV % GROWTH        REVENUE           REVENUE           EARNINGS

<S>                 <C>              <C>                 <C>              <C>
Q1  FY2000              14.5%        $ 33,900,000        38,800,000       $ 3,900,000

Q2  FY2000              28%            32,900,000        42,100,000         4,700,000

Q3  FY2000              32.4%          36,400,000        48,200,000         5,400,000

Q4  FY2000              26%            42,400,000        53,500,000         6,500,000
                                     ------------------------------       -----------


FY2000                  25.4%        $145,600,000      $182,600,000       $20,500,000
</TABLE>