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                                                                    EXHIBIT 10.4

                      PROJECT SOFTWARE & DEVELOPMENT, INC.
                        1994 EMPLOYEE STOCK PURCHASE PLAN


        1.      PURPOSE.

        The Project Software & Development, Inc. 1994 Employee Stock Purchase
Plan (the "Plan") is intended to provide a method whereby employees of Project
Software and Development, Inc. (the "Company") will have an opportunity to
acquire an ownership interest (or increase an existing ownership interest) in
the Company through the purchase of shares of the Common Stock of the Company.
It is the intention of the Company that the Plan qualify as an "employee stock
purchase plan" under Section 423 of the Internal Revenue Code of 1986, as
amended (the "Code"). The provisions of the Plan shall, accordingly, be
construed so as to extend and limit participation in a manner consistent with
the requirements of that section of the Code.

        2.      DEFINITIONS.

                (a)     "Compensation" means, for the purpose of any Offering
pursuant to this Plan, base pay in effect as of the Offering Commencement Date
(as hereinafter defined). Compensation shall not include any deferred
compensation other than contributions by an individual through a salary
reduction agreement to a cash or deferred plan pursuant to Section 401(k) of the
Code or to a cafeteria plan pursuant to Section 125 of the Code.

                (b)     "Board" means the Board of Directors of the Company.

                (c)     "Committee" means the Compensation Committee of the
Board.

                (d)     "Common Stock" means the common stock, $.01 par value
per share, of the Company.

                (e)     "Company" shall also include any Parent or Subsidiary of
Project Software & Development, Inc. designated by the Board, unless the context
otherwise requires.

                (f)     "Employee" means any person who is customarily employed
at least 20 hours per week and more than five months in a calendar year by the
Company.

                (g)     "Parent" shall mean any present or future corporation
which is or would constitute a "parent corporation" as that term is defined in
Section 424 of the Code.




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                (h)     "Subsidiary" shall mean any present or future
corporation which is or would constitute a "subsidiary corporation" as that term
is defined in Section 424 of the Code.

        3.      ELIGIBILITY.

                (a)     Participation in the Plan is completely voluntary.
Participation in any one or more of the offerings under the Plan shall neither
limit, nor require, participation in any other offering.

                (b)     Each employee shall be eligible to participate in the
Plan on the first Offering Commencement Date, as hereafter defined, following
the completion of three (3) full calendar months of continuous service with the
Company. Notwithstanding the foregoing, no employee shall be granted an option
under the Plan:

                        (i)     if, immediately after the grant, such employee
would own stock, and/or hold outstanding options to purchase stock, possessing
5% or more of the total combined voting power or value of all classes of stock
of the Company or any Parent or Subsidiary; for purposes of this Paragraph the
rules of Section 424(d) of the Code shall apply in determining stock ownership
of any employee; or

                        (ii)    which permits his rights to purchase stock under
all Section 423 employee stock purchase plans of the Company and any Parent or
Subsidiary to exceed $25,000 of the fair market value of the stock (determined
at the time such option is granted) for each calendar year in which such option
is outstanding; for purposes of this Paragraph, the rules of Section 423(b)(8)
of the Code shall apply.

        4.      OFFERING DATES.

                The right to purchase stock hereunder shall be made available by
a series of six-month offerings (the "Offering" or "Offerings") to employees
eligible in accordance with Paragraph 3 hereof. The Committee will, in its
discretion, determine the applicable date of commencement ("Offering
Commencement Date") and termination date ("Offering Termination Date") for each
Offering. Participation in any one or more of the Offerings under the Plan shall
neither limit, nor require, participation in any other Offering.

        5.      PARTICIPATION.

                Any eligible employee may become a participant by completing a
payroll deduction authorization form provided by the Company and filing it with
the office of the Company's Treasurer 20 days prior to an applicable Offering
Commencement Date, as



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determined by the Committee pursuant to Paragraph 4. A participant who obtains
shares of Common Stock in one Offering will be deemed to have elected to
participate in each subsequent Offering, provided such participant is eligible
to participate during each such subsequent Offering and provided that such
participant has not specifically elected not to participate in such subsequent
Offering. Such participant will also be deemed to have authorized the same
payroll deductions under Paragraph 6 hereof for each such subsequent Offering as
in the immediately preceding Offering; provided however, that, during the
enrollment period prior to each new Offering, the participant may elect to
change such participant's payroll deductions by submitting a new payroll
deduction authorization form.

        6.      PAYROLL DEDUCTIONS.

                (a)     At the time a participant files his authorization for a
payroll deduction, he shall elect to have deductions made from his pay on each
payday during any Offering in which he is a participant at a specified
percentage of his Compensation as determined on the applicable Offering
Commencement Date; said percentage shall be in increments of one percent up to a
maximum percentage of ten percent.

                (b)     Payroll deductions for a participant shall commence on
the applicable Offering Commencement Date when his authorization for a payroll
deduction becomes effective and subject to the last sentence of Paragraph 5
shall end on the Offering Termination Date of the Offering to which such
authorization is applicable unless sooner terminated by the participant as
provided in Paragraph 10.

                (c)     All payroll deductions made for a participant shall be
credited to his account under the Plan. A participant may not make any separate
cash payment into such account.

                (d)     A participant may withdraw from the Plan at any time
during the applicable Offering period.

        7.      GRANTING OF OPTION.

                (a)     Except as set forth in Paragraph 7(c) hereof, on the
Offering Commencement Date of each Offering, a participating employee shall be
deemed to have been granted an option to purchase a maximum number of shares of
the Common Stock equal to an amount determined as follows: 85% of the market
value per share of the Common Stock on the applicable Offering Commencement Date
shall be divided into an amount equal to the percentage of the employee's
Compensation which he has elected to have withheld (but no more than 10%)
multiplied by the employee's Compensation over the Offering period. Such market
value per share of the



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Common Stock shall be determined as provided in clause (i) of Paragraph 7(b).

                (b)     The option price of the Common Stock purchased with
payroll deductions made during each such Offering for a participant therein
shall be the lower of:

                        (i)     85% of the closing price per share on the
Offering Commencement Date as reported by a nationally recognized stock
exchange, or, if the Common Stock is not listed on such an exchange, as reported
by the National Association of Securities Dealers Automated Quotation System
("Nasdaq") National Market System or, if the Common Stock is not listed on the
Nasdaq National Market System, 85% of the mean of the bid and asked prices per
share on the Offering Commencement Date or, if the Common Stock is not traded
over-the-counter, 85% of the fair market value on the Offering Commencement Date
as determined by the Committee; and

                        (ii)    85% of the closing price per share on the
Offering Termination Date as reported by a nationally recognized stock exchange,
or, if the Common Stock is not listed on such an exchange, as reported by the
Nasdaq National Market System or, if the Common Stock is not listed on the
Nasdaq National Market System, 85% of the mean of the bid and asked prices per
share on the Offering Termination Date or, if the Common Stock is not traded
over-the-counter, 85% of the fair market value on the Offering Termination Date
as determined by the Committee.

        8.      EXERCISE OF OPTION.

                (a)     Unless a participant gives written notice to the
Treasurer of the Company as hereinafter provided, his option for the purchase of
Common Stock with payroll deductions made during any Offering will be deemed to
have been exercised automatically on the Offering Termination Date applicable to
such Offering for the purchase of the number of full shares of Common Stock
which the accumulated payroll deductions in his account at that time will
purchase at the applicable option price (but not in excess of the number of
shares for which options have been granted the employee pursuant to Paragraph
7(a)), and any excess in his account at that time, other than amounts
representing fractional shares, will be returned to him.

                (b)     Fractional shares will not be issued under the Plan and
any accumulated payroll deductions which would have been used to purchase
fractional shares shall be automatically carried forward to the next Offering
unless the participant elects, by written notice to the Treasurer of the
Company, to have the excess cash returned to him.




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        9.      DELIVERY.

                The Company will deliver to each participant (as promptly as
possible after the appropriate Offering Termination Date), a certificate
representing the Common Stock purchased upon exercise of his option.

        10.     WITHDRAWAL AND TERMINATION.

                (a)     Prior to the Offering Termination Date for an Offering,
any participant may withdraw the payroll deductions credited to his account
under the Plan for such Offering by giving written notice to the Treasurer of
the Company. All of the participant's payroll deductions credited to such
account will be paid to him promptly after receipt of notice of withdrawal,
without interest, and no future payroll deductions will be made from his pay
during such Offering. The Company will treat any attempt to borrow by a
participant on the security of accumulated payroll deductions as an election to
withdraw such deductions.

                (b)     Except as set forth in Paragraphs 6(d) and 7(c), a
participant's election not to participate in, or withdrawal from, any Offering
will not have any effect upon his eligibility to participate in any succeeding
Offering or in any similar plan which may hereafter be adopted by the Company.

                (c)     Upon termination of the participant's employment for any
reason, including retirement but excluding death, the payroll deductions
credited to his account will be returned to him, or, in the case of his death,
to the person or persons entitled thereto under Paragraph 14.

                (d)     Upon termination of the participant's employment because
of death, his beneficiary (as defined in Paragraph 14) shall have the right to
elect, by written notice given to the Company's Treasurer prior to the
expiration of a period of 90 days commencing with the date of the death of the
participant, either:

                        (i)     to withdraw all of the payroll deductions
credited to the participant's account under the Plan; or

                        (ii)    to exercise the participant's option for the
purchase of stock on the Offering Termination Date next following the date of
the participant's death for the purchase of the number of full shares which the
accumulated payroll deductions in the participant's account at the date of the
participant's death will purchase at the applicable option price (subject to the
limitation contained in Paragraph 7(a)), and any excess in such account will be
returned to said beneficiary. In the event that no such written notice of
election shall be duly received by the 




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office of the Company's Treasurer, the beneficiary shall automatically be deemed
to have elected to withdraw the payroll deductions credited to the participant's
account at the date of the participant's death and the same will be paid
promptly to said beneficiary.

        11.     INTEREST.

                No interest will be paid or allowed on any money paid into the
Plan or credited to the account of any participating employee.

        12.     STOCK.

                (a)     The maximum number of shares of Common Stock available
for issuance and purchase by employees under the Plan, subject to adjustment
upon changes in capitalization of the Company as provided in Paragraph 17, shall
be 150,000 shares of Common Stock, par value $.01 per share, of the Company. If
the total number of shares for which options are exercised on any Offering
Termination Date in accordance with Paragraph 8 exceeds the maximum number of
shares for the applicable Offering, the Company shall make a pro rata allocation
of the shares available for delivery and distribution in an equitable manner,
and the balances of payroll deductions credited to the account of each
participant under the Plan shall be returned to the participant.

                (b)     The participant will have no interest in stock covered
by his option until such option has been exercised.

        13.     ADMINISTRATION.

                The Plan shall be administered by the Committee. The
interpretation and construction of any provision of the Plan and adoption of
rules and regulations for administering the Plan shall be made by the Committee.
Determinations made by the Committee with respect to any matter or provision
contained in the Plan shall be final, conclusive and binding upon the Company
and upon all participants, their heirs or legal representatives. Any rule or
regulation adopted by the Committee shall remain in full force and effect unless
and until altered, amended, or repealed by the Committee.

        14.     DESIGNATION OF BENEFICIARY.

                A participant shall file with the Treasurer of the Company a
written designation of a beneficiary who is to receive any Common Stock and/or
cash under the Plan. Such designation of beneficiary may be changed by the
participant at any time by written notice. Upon the death of a participant and
upon receipt by the Company of proof of the identity and existence at the
participant's death of a beneficiary validly designated by him 




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under the Plan, the Company shall deliver such Common Stock and/or cash to such
beneficiary. In the event of the death of a participant and in the absence of a
beneficiary validly designated under the Plan who is living at the time of such
participant's death, the Company shall deliver such Common Stock and/or cash to
the executor or administrator of the estate of the participant. No beneficiary
shall prior to the death of the participant by whom he has been designated,
acquire any interest in the Common Stock and/or cash credited to the participant
under the Plan.

        15.     TRANSFERABILITY.

                Neither payroll deductions credited to a participant's account
nor any rights with regard to the exercise of an option or to receive Common
Stock under the Plan may be assigned, transferred, pledged, or otherwise
disposed of in any way by the participant other than by will or the laws of
descent and distribution. Any such attempted assignment, transfer, pledge, or
other disposition shall be without effect, except that the Company may treat
such act as an election to withdraw funds in accordance with Paragraph 10.

        16.     USE OF FUNDS.

                All payroll deductions received or held by the Company under
this Plan may be used by the Company for any corporate purpose, and the Company
shall not be obligated to segregate such payroll deductions.

        17.     EFFECT OF CHANGES OF COMMON STOCK.

                If the Company shall subdivide or reclassify the Common Stock
which has been or may be subject to options under this Plan, or shall declare
thereon any dividend payable in shares of such Common Stock, or shall take any
other action of a similar nature affecting such Common Stock, then the number
and class of shares of Common Stock which may thereafter be subject to options
under the Plan (in the aggregate and to any participant) shall be adjusted
accordingly and in the case of each option outstanding at the time of any such
action, the number and class of shares which may thereafter be purchased
pursuant to such option and the option price per share shall be adjusted to such
extent as may be determined by the Committee, with the approval of independent
public accountants and counsel, to be necessary to preserve the rights of the
holder of such option.

        18.     AMENDMENT OR TERMINATION.

                The Board may at any time terminate or amend the Plan. No such
termination shall affect options previously granted, nor may an amendment make
any change in any option theretofore 




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granted which would adversely affect the rights of any participant holding
options under the Plan without the consent of such participant.

        19.     NOTICES.

                All notices or other communications by a participant to the
Company under or in connection with the Plan shall be deemed to have been duly
given when received by the Treasurer of the Company.

        20.     MERGER OR CONSOLIDATION.

                If the Company shall at any time merge into or consolidate with
another corporation, the holder of each option then outstanding will thereafter
be entitled to receive at the next Offering Termination Date upon the exercise
of such option, in lieu of the number of shares of Common Stock as to which such
option shall be exercisable, the number and class of shares of stock or other
securities or property to which such holder would have been entitled pursuant to
the terms of the agreement of merger or consolidation if, immediately prior to
such merger or consolidation, such holder had been the holder of record of a
number of shares of Common Stock equal to the number of shares for which such
option was exercisable. In accordance with this Paragraph and Paragraph 17, the
Committee shall determine the kind and amount of such securities or property
which such holder of an option shall be entitled to receive. A sale of all or
substantially all of the assets of the Company shall be deemed a merger or
consolidation for the foregoing purposes.

        21.     APPROVAL OF STOCKHOLDERS.

                The Plan is subject to the approval of the stockholders of the
Company at their next annual meeting or at any special meeting of the
stockholders for which one of the purposes shall be to act upon the Plan.

        22.     GOVERNMENTAL AND OTHER REGULATIONS.

                The Plan, and the grant and exercise of the rights to purchase
shares hereunder, and the Company's obligation to sell and deliver shares upon
the exercise of rights to purchase shares, shall be subject to all applicable
federal, state and foreign laws, rules and regulations, and to such approvals by
any regulatory or governmental agency as may, in the opinion of counsel for the
Company, be required. The Plan shall be governed by, and construed and enforced
in accordance with, the provisions of Sections 421, 423 and 424 of the Code and
the substantive laws of The Commonwealth of Massachusetts. In the event of any
inconsistency between such provisions of the Code and any such laws, such
provisions of the Code shall govern to the extent 




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necessary to preserve favorable federal income tax treatment afforded employee
stock purchase plans under Section 423 of the Code.


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