<PAGE>

                                                                   Exhibit 10.15
                              EMPLOYMENT AGREEMENT


          AGREEMENT made as of this 1/st/ day of April, 2001, by and between
Patrick H. Kareiva (the "Employee") and Workgroup Technology Corporation, a
Delaware corporation with its principal place of business at 91 Hartwell Avenue,
Lexington, MA 02421 (the "Company").

          NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, and in consideration of the mutual
covenants and obligations herein contained, the parties hereto agree as follows:

          1.   Position and Responsibilities. During the term of this
               -----------------------------
Agreement, the Employee agrees to serve as the President and Chief Executive
Officer of the Company. The Employee shall at all times report to, and his
activities shall at all times be subject to the direction and control of the
Board of Directors of the Company (the "Board of Directors"), and the Employee
shall exercise such powers and comply with and perform, faithfully and to the
best of his ability, such directions and duties in relation to the business and
affairs of the Company as may from time to time be vested in or requested of
him. During the period of Employee's employment by the Company, Employee shall
devote substantially all of his time and best efforts to the business of the
Company. If Employee shall be elected to other offices of the Company or any of
its affiliates, he shall serve in such positions without further compensation
than provided for in this Agreement.

          2.   Compensation: Salary, Bonuses and Other Benefits.  During the
               ------------------------------------------------
term of this Agreement, the Company shall pay the Employee the following
compensation:

          (A)  Salary. In consideration of the services to be rendered by
               ------
the Employee to the Company, the Company shall pay to the Employee a monthly
salary of Thirty Thousand Dollars ($30,000.00) Such salary shall be paid in
conformity with the Company's customary practices for executive compensation, as
such practices shall be established or modified from time to time.

          (B)  Benefits. During the Employee's employment, the Employee
               --------
will be eligible to participate in the Company's standard benefit plans to the
same extent as, and subject to the same terms, conditions and limitations
applicable to, other employees of the Company of similar rank and tenure.
Nothing contained in this Agreement shall prevent the Company from amending or
terminating any employee benefit plan or program at any time in any manner or
from changing carriers or from effecting modifications in insurance coverage for
the Employee.

          (C)  Bonuses. During each financial quarter ("Quarter"), the Employee
               -------
shall be eligible to receive a bonus based on the total software license revenue
for the Quarter (the "Total Software License Revenue Bonus"). The Total Software
License Revenue Bonus, if any, shall be calculated as 5% of the Company's "total
software license revenue" as reported on the Company's regularly prepared
financial statements. Any such Total Software License Revenue Bonus shall be
earned as of the last day of a Quarter. The Total Software License Revenue
Bonus, if any, shall be paid on or before the last day of the calendar month
immediately following the Quarter in which it is earned. Notwithstanding the
foregoing, the Total Software License Revenue Bonus earned by Employee in any
Quarter shall not exceed 15% of Employee's then current annual salary.

          (D)  Expenses. The Company shall pay or reimburse the Employee for all
               --------
reasonable business expenses incurred or paid by the Employee in the performance
of his duties and responsibilities hereunder
<PAGE>

                                      -2-

in accordance with the expense policies of the Company as they may be
established or modified from time to time.

          (E)  Vacation. During the term hereof, the Employee shall be entitled
               --------
to four (4) weeks of vacation per calendar year to be earned at the rate of one
week for each quarter during which Employee is an employee in good standing on
the first day of such quarter. Vacation will be taken at such times and
intervals as shall be agreed to by the Company and the Employee in their
reasonable discretion.

         (F) All payments in this Section 2 shall be subject to all applicable
federal, state and local withholding, payroll and other taxes.

          3.   Term. Subject to the earlier termination as hereafter provided in
               ----
Section 4, the term of this Agreement shall commence on April 1, 2001 and shall
continue until March 31, 2003 (the "Initial Term"), provided, however, the
Employee's employment under this Agreement shall be automatically renewed
thereafter for successive one (1) month terms unless ten (10) calendar days
prior to the expiration of the Initial Term or any renewal term, either party
shall give written notice of non-renewal to the other.

          4.   Termination.  The Employee's employment under this Agreement
               -----------
may be terminated as follows:

          (A)  By Termination of the Agreement. If this Agreement is terminated
               -------------------------------
by the Employee as set forth in Section 3 hereof, the Employee shall be entitled
to no further payments, severance or other benefits after the termination date
of the Agreement except as required by law.

          (B)  At the Employee's Option. The Employee may terminate his
               ------------------------
employment hereunder at any time during the Initial Term of this Agreement by
giving at least thirty (30) calendar days' advance written notice to the
Company. In the event of such a termination at the Employee's option, the
Company may accelerate Employee's departure date and shall have no obligation to
pay Employee after his actual departure date. In the event of such a termination
at the Employee's option, the Employee shall be entitled to no further payments,
severance or other benefits after the effective date of his termination, except
as otherwise required by law.

          (C)  At the election of the Company for Cause. The Company may,
               ----------------------------------------
immediately and unilaterally, terminate the Employee's employment hereunder "for
cause" at any time during the term of this Agreement by providing Employee
written notice of termination "for cause." Termination of the Employee's
employment by the Company shall constitute a termination "for cause" under this
Section 4(C) if such termination is for one or more of the following causes:

               (i)      the willful failure or refusal of the Employee to render
                        services to the Company in accordance with the duties of
                        Chief Executive Officer;

               (ii)     the commission by the Employee of an act of fraud or
                        embezzlement;

               (iii)    the commission of illegal activity by the Employee; or

               (iv)     the Employee's breach of the terms of this Agreement.

          In the event of a termination "for cause" pursuant to the provisions
of clauses (i) through (iv) above, inclusive, the Employee shall be entitled to
no further payments, severance or other benefits
<PAGE>

                                      -3-

except as otherwise required by law. Notwithstanding the foregoing, the Employee
shall be entitled to receive a portion of a Total Software License Revenue Bonus
pro rated for the number of days the Employee was employed by the Company during
the Quarter in which such termination occurs. Payment of such bonus shall be
made within (5) business days after the date the Company releases its regularly
prepared financial statements to the public.

          (D)  At the Election of the Company for Reasons Other than for Cause.
               ---------------------------------------------------------------
The Company may terminate the Employee's employment hereunder at any time during
the Initial Term of this Agreement without cause by giving thirty (30) calendar
days' advance written notice to the Employee of the Company's election to
terminate. At the Company's sole option, the Company may give Employee thirty
(30) days pay in lieu of such notice. During such thirty (30) day period, the
Employee will be available on a full-time basis for the benefit of the Company
to assist the Company in making the transition to a successor officer of the
Company. In the event of the Company's termination of Employee either under
Section 3 hereof, or under this Section 4(D), then, the Employee shall be paid a
lump sum payment equivalent to twelve (12) months of the Employee's then current
salary, to be paid on the Company's next regularly scheduled payroll date. In
addition to the foregoing payment, the Employee shall also be entitled to
receive a portion of a Total Software License Revenue Bonus pro rated for the
number of days the Employee was employed by the Company during the Quarter in
which such termination occurs and payment of such bonus shall be made within (5)
business days after the date the Company releases its regularly prepared
financial statements to the public. For purposes of calculating the pro rata
bonus pursuant to this paragraph, if the Company gives the Employee thirty (30)
days pay in lieu of notice, his termination shall be deemed to have occurred
thirty calendar days from his last day of employment.

          (E)  Liquidity Event. In the event of a Liquidity Event, the
               ---------------
Employee's employment hereunder shall automatically terminate upon the effective
date of the Liquidity Event, except in the case of the sale of all or
substantially all of the assets of the Company, in which case Employee's
employment shall terminate thirty (30) calendar days after the closing of such
sale. In the event of the Company's termination of Employee under this Section
4(E), then the Employee shall be paid a lump sum payment equivalent to twelve
(12) months of the Employee's then current salary, to be paid on the Company's
next regularly scheduled payroll date. In addition to the foregoing payment, the
Employee shall also be entitled to receive a portion of a Total Software License
Revenue Bonus pro rated for the number of days the Employee was employed by the
Company during the Quarter in which such termination occurs and payment of such
bonus shall be made within (5) business days after the Company releases its
regularly prepared financial statements to the public. For the purposes of this
Agreement, "Liquidity Event" means (i) a sale of all or substantially all of the
assets of the Company; (ii) a merger or consolidation of the Company with or
into any other corporation, unless the Company is the surviving entity and the
shareholders of the Company immediately prior to such event continue to own a
majority of the outstanding shares of the Company after such event; or (iii) the
transfer, in a single transaction or a series of related transactions, of a
majority of the outstanding shares of the Company.

          5.   Survival of Certain Provisions. Provisions of this Agreement
               ------------------------------
shall survive any termination of employment of this Agreement if so provided
herein or if necessary or desirable to fully accomplish the purposes of such
provision. Without limiting the foregoing, the obligations of the parties under
Sections 2, 4, 6 and 7 hereof expressly survive any termination of employment or
termination of this Agreement.

          6.   Employee Noncompetition, Nonsolicitation, Nondisclosure and
               -----------------------------------------------------------
Developments Agreement. As a condition of his employment by the Company, the
----------------------
Employee shall enter into the Employee Noncompetition, Nonsolicitation,
Nondisclosure and Developments Agreement (the "Employee Noncompetition,
Nonsolicitation, Nondisclosure and Developments Agreement"), an original
<PAGE>

                                      -4-

counterpart of which shall be attached hereto as Attachment A and incorporated
                                                 ------------
herein as if reproduced in its entirety.

          7.   Indemnification. The Employee shall be entitled to
               ---------------
indemnification in accordance with the provisions of Article TENTH of the Second
Amended and Restated Certificate of Incorporation of the Company, as in effect
on the date hereof. During the period of Employee's employment with the Company,
the Company shall not amend the provisions of said Article TENTH without the
consent of the Employee. During the period of Employee's employment with the
Company, the Company shall maintain its existing directors and officers
insurance policy, with its current $5 million policy limits, for the benefit of
the Employee. The Employee shall also be entitled to all other additional rights
of indemnification and exculpation, if any, as may be provided by law or by
Company policy in his capacity as an officer and employee of the Company.

          8.   Consent and Waiver by Third Parties. The Employee hereby
               -----------------------------------
represents and warrants that he has obtained all waivers and/or consents from
third parties which are necessary to enable him to enjoy employment with the
Company on the terms and conditions set forth herein and to execute and perform
this Agreement without being in conflict with any other agreement, obligation or
understanding with any such third party. The Employee represents that he is not
bound by any agreement or any other existing or previous business relationship
which conflicts with, or may conflict with, the performance of his obligations
hereunder or prevent the full performance of his duties and obligations
hereunder.

          9.   Due Authorization. The Company represents to Employee that this
               -----------------
Agreement has been duly authorized by all necessary corporate action and that,
upon execution of this Agreement by the outside Directors of the Company, it
will be a duly authorized, executed and delivered agreement of the Company,
enforceable against it in accordance with its terms.

          10.  Governing Law. This Agreement, the employment relationship
               -------------
contemplated herein and any claim arising from such relationship, whether or not
arising under this Agreement, shall be governed by and construed in accordance
with the internal laws of the Commonwealth of Massachusetts, without giving
effect to the principles of choice of law or conflicts of laws of such
Commonwealth and this Agreement shall be deemed to be performable in
Massachusetts. Any claims or legal actions by one party against the other
arising out of the relationship between the parties contemplated herein (whether
or not arising under this Agreement) shall be commenced or maintained in any
state or federal court located in Massachusetts, and Employee and Company hereby
submit to the jurisdiction and venue of any such court.

          11.  Severability. In case any one or more of the provisions contained
               ------------
in this Agreement for any reason shall be held to be invalid, illegal or
unenforceable in any respect, such invalidity, illegality or unenforceability
shall not affect any other provision of this Agreement. Moreover, if one or more
of the provisions contained in this Agreement shall for any reason be held to be
excessively broad as to scope, activity, subject or otherwise so as to be
unenforceable at law, such provision or provisions shall be construed and
reformed by the appropriate judicial body by limiting or reducing it or them, so
as to be enforceable to the maximum extent compatible with the applicable law as
it shall then appear.

          12.  Remedies Upon Breach. The Employee agrees that any breach of this
               --------------------
Agreement by him will cause irreparable damage to the Company and that in the
event of such breach the Company shall have, in addition to any and all remedies
of law, the right to an injunction, specific performance or other equitable
relief to prevent the violation of Employee's obligations hereunder.
<PAGE>

                                      -5-

          13.  Waivers and Modifications. This Agreement may be modified, and
               -------------------------
the rights, remedies and obligations contained in any provision hereof may be
waived, only in accordance with this Section 13. No waiver by either party of
any breach by the other or any provision hereof shall be deemed to be a waiver
of any later or other breach thereof or as a waiver of any other provision of
this Agreement. This Agreement sets forth all of the terms of the understandings
between the parties with reference to the subject matter set forth herein and
may not be waived, changed, discharged or terminated orally or by any course of
dealing between the parties, but only by an instrument in writing signed by the
party against whom any waiver, change, discharge or termination is sought. No
modification or waiver by the Company shall be effective without the consent of
the majority of the outside Directors of the Company.

          14.  Assignment. The Employee may not assign any of his rights or
               ----------
delegate any of his duties or obligations under this Agreement provided,
however, that the rights of Employee hereunder shall inure to the benefit of his
legal representatives and heirs in the event of his death or disability. The
rights and obligations of the Company under this Agreement shall inure to the
benefit of, and shall be binding upon, the successors and assigns of the
Company.

          15.  Entire Agreement. This Agreement and the Employee Noncompetition,
               ----------------
Nonsolicitation, Nondisclosure and Developments Agreement constitute the entire
understanding of the parties relating to the subject matter hereof and supersede
and cancel all agreements, written or oral, made prior to the date hereof
between the Employee and the Company.

          16.  Notices. All notices hereunder shall be in writing and shall be
               -------
delivered in person or mailed by certified or registered mail, return receipt
requested, addressed as follows:

          If to the Company, to:                     Workgroup Technology
                                                     Corporation
                                                     91 Hartwell Avenue
                                                     Lexington, MA 02421
                                                     Attention: Board of
                                                     Directors

          With a Copy to:                            Andrew E. Taylor, Jr. Esq.
                                                     Testa, Hurwitz & Thibeault,
                                                     LLP
                                                     125 High Street
                                                     Boston, MA 02110

          If to the Employee, to:                    Patrick H. Kareiva
                                                     Workgroup Technology
                                                     Corporation
                                                     91 Hartwell Avenue
                                                     Lexington, MA 02421

          17. Counterparts. This Agreement may be executed in two or more
              ------------
counterparts, each of which shall be deemed to be an original, but all of which
together shall constitute one and the same instrument.

          18. Section Headings. The descriptive section headings herein have
              ----------------
been inserted for convenience only and shall not be deemed to define, limit, or
otherwise affect the construction of any provision hereof.
<PAGE>

                                      -6-

         IN WITNESS WHEREOF, the parties hereto have executed this Employment
Agreement effective as of the date first above written.

                                     WORKGROUP TECHNOLOGY CORPORATION



                                     By:    /s/ James M. McConnell
                                            -----------------------------------
                                     Title: Director




                                     By:    /s/ Douglas A. Catalano
                                            -----------------------------------
                                     Title: Director




                                     By:    /s/ Patrick H. Kareiva
                                            -----------------------------------
                                     Patrick H. Kareiva
<PAGE>

                                                                    Attachment A

                       WORKGROUP TECHNOLOGY CORPORATION

            EMPLOYEE NONCOMPETITION, NONSOLICITATION, NONDISCLOSURE
                          AND DEVELOPMENTS AGREEMENT

     In consideration for and as a condition of my initial or continuing
employment by WORKGROUP TECHNOLOGY CORPORATION, or any of its subsidiaries,
subdivisions or affiliates (hereafter, the "Company"), and the compensation
received by me from the Company from time to time, I hereby agree with the
Company, as follows:

     1.   Noncompetition Covenants. During my employment with the Company, I
          ------------------------
will devote my full time and best efforts to the business of the Company. I
further agree that during the period of my employment by the Company and for a
period of one (1) year thereafter, regardless of the reason for the termination
of such employment, I will not, directly or indirectly, whether alone or as a
partner, joint venturer, officer, director, consultant, employee, independent
contractor or stockholder of any company or business organization, engage in any
business activity and/or accept employment with any person or entity, which is
or may be directly or indirectly in competition with the products or services
being marketed, promoted, distributed, developed, planned, sold or otherwise
provided by the Company. The ownership by me of not more than one percent of the
shares of capital stock of any corporation having a class of equity securities
traded on a national securities exchange or on NASDAQ shall not be deemed, in
and of itself, to violate this section.

     2.   Nonsolicitation.
          ---------------

     (a)  During the period of my employment by the Company and for a period of
one (1) year after termination of such employment, I will not directly or
indirectly either for myself or for any other person, business, partnership,
association, firm, company or corporation, call upon, solicit, divert or take
away or attempt to solicit, divert or take away, any of the customers,
prospective customers or business of the Company made known to me during my
employment by the Company on behalf of a business in competition with the
Company. For purposes of this Agreement, "prospective customers" shall include
those customers being actively solicited by the Company during the period of my
employment with the Company.

     (b)  During my employment with the Company and for a period of one (1) year
thereafter, I will not hire or engage (or be involved in the hiring of) any
employee of the Company or induce, solicit, or recruit, or attempt to induce,
solicit, or recruit, any employee of the Company to terminate his or her
employment or otherwise cease his or her relationship with the Company.

     3.   Nondisclosure Obligations.
          -------------------------

     (a)  I will not at any time, whether during or after the termination of my
employment for any reason whatsoever, reveal to any person or entity any of the
trade secrets or confidential information concerning the Company's organization,
research and development activities, source
<PAGE>

                                      -2-

code for software products, technical and engineering data and specifications,
know-how, sales, marketing, field service, and maintenance operations, marketing
plans and strategies, pricing policies, customer lists and accounts, existing
and future products and services, inventions, systems, databases, plans and
proposals, business, finances or financial information of the Company, except as
may be required in the ordinary course of performing my duties as an employee of
the Company. Further, I shall keep secret all matters entrusted to me and shall
not use or disclose any such information in any manner which may injure or cause
loss or may be calculated to injure or cause loss, whether directly or
indirectly, to the Company.

     (b)  I agree that during my employment I shall not make, use or permit to
be used any Company documentation (as defined below) otherwise than for the
benefit of the Company. I further agree that I shall not, after the termination
of my employment for any reason, use or permit others to use any such Company
documentation, it being agreed that all Company documentation shall be and
remain the sole and exclusive property of the Company. Immediately upon the
termination of my employment for any reason I shall deliver all of the
foregoing, and all copies thereof, to the Company, at its main office. For
purposes of this Agreement, the term "Company documentation" shall mean notes,
memoranda, reports, proposals, lists, correspondence, records, drawings,
sketches, blueprints, specifications, software programs, data, source code,
documentation or other materials of any nature and in any form, whether written,
printed, or in digital format or otherwise, relating to any matter within the
scope of the business of the Company or concerning any of its dealings or
affairs.

     (c)  I recognize that the Company has received and in the future will
receive from third parties their confidential or proprietary information subject
to a duty on the Company's part to maintain the confidentiality of such
information and to use it only for certain limited purposes. I agree that I owe
the Company and such third parties, during the term of my employment and
thereafter, regardless of the reason for my termination of employment, a duty to
hold all such confidential or proprietary information in the strictest of
confidence and not to disclose it to any person, firm or corporation (except as
necessary in carrying out my work for the Company consistent with the Company's
agreement with such third party) or to use it for the benefit of anyone other
than for the Company or such third party (consistent with the Company's
agreement with such third party) without the express written authorization of
the Board of Directors of the Company.

     4.   Assignment of Developments. If at any time or times during my
          --------------------------
employment, I shall (either alone or with others) make, conceive, create,
discover, invent or reduce to practice any Development (as defined below) that:
(a) relates to the business of the Company or any customer of or supplier to the
Company or any of the products or services being developed, manufactured or sold
by the Company or which may be used in relation therewith; or (b) results from
tasks assigned to me by the Company; or (c) results from the use of premises or
personal property (whether tangible or intangible) owned, leased or contracted
for by the Company, such Developments and the benefits thereof are and shall
immediately become the sole and absolute property of the Company and its
assigns, as works made for hire or otherwise. I shall promptly disclose to the
Company (or any persons designated by it) each such Development. I hereby assign
any rights (including, but not limited to, any inventions, patentable subject
matter, copyrights and trademarks) I may have or acquire in the Developments and
benefits and/or rights
<PAGE>

                                      -3-

resulting therefrom to the Company and its assigns without further compensation
and shall communicate, without cost or delay, and without disclosing to others
the same, all available information relating thereto (with all necessary plans
and models) to the Company. For purposes of this Agreement, the term
"Development" shall mean any software programs, source code, software and
systems documentation, designs, systems, trade secrets, specifications,
flowcharts, logic diagrams, field service reports, engineering reports,
technical data, know-how and specifications, management reports, internal
reports and memoranda, customer lists, marketing plans, pricing policies,
inventions, discoveries, improvements, modifications, intellectual property and
any rights or any interest therein (whether or not patentable or registerable
under copyright, trademark or similar statutes.)

     I will, during my employment and at any time thereafter, regardless of the
reason for the termination of my employment, at the request and cost of the
Company, promptly sign, execute, make and do all such deeds, documents, acts and
things as the Company and its duly authorized officers may reasonably require:

               (a)  to apply for, obtain, register and vest in the name of the
          Company alone (unless the Company otherwise directs) letters patent,
          copyrights, trademarks or other analogous protection in any country
          throughout the world and when so obtained or vested to renew and
          restore the same; and

               (b)  to defend any judicial, opposition or other proceedings in
          respect of such applications and any judicial, opposition or other
          proceedings or petitions or applications for revocation of such
          letters patent, copyright, trademark or other analogous protection.

     In the event the Company is unable, after reasonable effort, to secure my
signature on any application for letters patent, copyright or trademark
registration or other documents regarding any legal protection relating to a
Development, whether because of my physical or mental incapacity or for any
other reason whatsoever, I hereby irrevocably designate and appoint the Company
and its duly authorized officers and agents as my agent and attorney-in-fact, to
act for and in my behalf and stead to execute and file any such application or
applications or other documents and to do all other lawfully permitted acts to
further the prosecution and issuance of letters patent, copyright or trademark
registrations or any other legal protection thereon with the same legal force
and effect as if executed by me.

     I agree to keep and maintain adequate and current written records of all
Developments made by me (solely or jointly with others) during the term of my
employment with the Company. The records will be in the form of notes, sketches,
drawings, and any other format that may be specified by the Company at all
times.

     5.   Excluded Developments. I represent that the Developments identified in
          ---------------------
the pages, if any, attached hereto as Exhibit A comprise all the unpatented and
unregistered copyrightable Developments which I have made, conceived or created
prior to my employment by the Company, which Developments are excluded from this
Agreement. I understand that it is only necessary to list the title and purpose
of such Developments but not details thereof. IF
<PAGE>

                                      -4-

THERE ARE ANY SUCH UNPATENTED OR UNREGISTERED COPYRIGHTABLE INVENTIONS TO BE
EXCLUDED, THE UNDERSIGNED SHOULD INITIAL HERE. OTHERWISE IT WILL BE DEEMED THAT
THERE ARE NO SUCH EXCLUSIONS. __________.

     6.   Absence of Conflicting Agreements. I understand that the Company does
          ---------------------------------
not desire to acquire from me trade secrets, know-how or confidential business
information to which I may have been exposed by others. Accordingly, I agree
that I will not during my employment with the Company improperly use or disclose
any proprietary information or trade secrets of my former employers or of any
other third parties, and that I will not bring onto the premises of the Company
any unpublished document or any property belonging to my former employers or of
any other third party, unless consented to in writing by said employers or third
parties. I represent that I am not bound by any agreement or any other existing
or previous business relationship which conflicts with or prevents the full
performance of my duties and obligations to the Company during the course of my
employment.

     I have attached hereto a copy of each agreement, if any, which presently
relates to any post-employment obligations by me to any former employers. (Such
copy specifies the other contracting party or employer, the date of such
agreement, the date of termination of any employment.) IF THERE ARE ANY SUCH
AGREEMENTS, THE UNDERSIGNED SHOULD INITIAL HERE. OTHERWISE IT WILL BE DEEMED
THAT THERE ARE NO SUCH AGREEMENTS. __________________.

     7.   Consent to use of name, picture. I agree to and consent to the use of
          -------------------------------
my name, picture, signature, voice, image, and/or likeness by the Company for
business-related purposes. Further, I waive all claims I have against the
Company and its officers, employees, and agents arising out of the Company's
business-related use, adaptation, reproduction, modification, distribution,
exhibition, or other commercial exploitation of the undersigned's name, picture,
signature, voice, image, and/or likeness, including but not limited to right of
privacy, right of publicity and celebrity, use of voice, name or likeness, and
copyright infringement. I further represent and warrant that I have not
heretofore made any contract or commitment in conflict with this consent and
waiver.

     8.   Return of Materials. I agree that, at the time of leaving the employ
          -------------------
of the Company for any reason, I will deliver to the Company (and will not keep
in my possession or deliver to anyone else) any and all Company documentation,
keys, materials, equipment, devices, other documents or property, or
reproductions of any aforementioned items belonging to the Company, its
successors or assigns. I further agree to return to or otherwise inform the
Company of all means of access to any account, database, or computer system of
the Company (whether personal to me or public, published or unpublished,
standard or backdoor, including all account names, passwords, access codes,
unique personal identification numbers, any code kept secret and any other means
allowing employee access to Company data or documentation).

     9.   Remedies Upon Breach. I agree that any breach of this Agreement by me
          --------------------
will cause irreparable damage to the Company and that in the event of such
breach, the Company shall have, in addition to any and all remedies of law, the
right to an injunction, specific
<PAGE>

                                      -5-

performance or other equitable relief to prevent the violation of my obligations
hereunder, without showing or proving actual damages or exhausting any Company
remedy in the form of money damages, and without having to post a bond or any
other security.

     10.  No Employment Obligations. I understand that this Agreement does not
          -------------------------
create an obligation on the Company or any other person to continue my
employment with the Company. I further acknowledge and agree that my employment
is at-will, and that both I and the Company can terminate my employment without
reason and at any time.

     11.  No Waiver. Any waiver by the Company of a breach of any provision of
          ---------
this Agreement shall not operate or be construed as a waiver of any subsequent
breach of such provision or any other provision hereof. Each provision herein
shall be treated as a separate and independent clause, and the unenforceability
of any one clause shall in no way impair the enforceability of any of the other
clauses herein. Moreover, if one or more of the provisions contained in this
Agreement shall for any reason be held to be excessively broad as to scope,
activity or subject matter so as to be unenforceable at law, such provision or
provisions shall be construed and reformed by the appropriate judicial body by
limiting and reducing it of them, so as to be enforceable to the maximum extent
compatible with the applicable law as it shall then appear. I hereby further
agree that the language of all parts of this Agreement shall in all cases be
construed as a whole according to its fair meaning and not strictly for or
against any of the parties.

     12.  Survival of Obligations. This Agreement shall be effective as of the
          -----------------------
date entered below. My obligations under this Agreement shall survive the
termination of my relationship with the Company regardless of the manner of such
termination.

     13.  Assignment by Company. The term "Company" shall include Workgroup
          ---------------------
Technology Corporation, a Delaware corporation, and any of its subsidiaries,
subdivisions or affiliates. The Company shall have the right to assign this
Agreement to its successors and assigns, and all covenants and agreements
hereunder shall inure to the benefit of and be enforceable by said successors or
assigns.

     14.  Entire Agreement. Subject to any prior confidentiality, non-disclosure
          ----------------
and/or intellectual property obligations I owe to the Company, this Agreement
sets forth the entire agreement and understanding between the Company and me
relating to the subject matter herein and supersedes all prior discussions,
agreements and understandings between us respecting the subject matter hereof.
Any amendment to or modification of this Agreement, or any waiver of any
provision hereof, shall be in writing and signed by the Company. Any subsequent
change or changes in my duties, salary compensation or employment status will
not affect the validity or scope of this Agreement.

     15.  Governing Law. This Agreement shall be governed by, and construed in
          -------------
accordance with, the laws of the Commonwealth of Massachusetts and shall in all
respects be interpreted, enforced and governed under the internal and domestic
laws of such state, without giving effect to the principles of conflicts of laws
of such state. Any claims or legal actions by one party against the other
arising out of the relationship between the parties contemplated
<PAGE>

                                      -6-

herein (whether or not arising under this Agreement) shall be governed by the
laws of Massachusetts and shall be commenced and maintained in any state or
federal court located in Massachusetts, and both parties hereby submit to the
jurisdiction and venue of any such court.

     16.  Reasonableness of Agreement. I recognize and agree that the
          ---------------------------
enforcement of this Agreement is necessary to ensure the preservation,
protection and continuity of the business, confidential business information,
trade secrets and goodwill of the Company. I further agree that, due to the
proprietary nature of the Company's business, the restrictions set forth in
Sections 1, 2, 3, 4 and 7 of this Agreement are reasonable as to duration and
scope.

     IN WITNESS WHEREOF, the undersigned Employee and the Company have executed
this Agreement as of this 31/st/ day of May, 2000.

WORKGROUP TECHNOLOGY                              EMPLOYEE:
 CORPORATION:


By: /s/ James M. Carney                           /s/ Patrick H. Kareiva
    ----------------------------------            ------------------------------
                                                  Signature of Employee

Title: Chairman of the Board                      Patrick H. Kareiva
       -------------------------------            ------------------------------
                                                  Print Name of Employee
<PAGE>

                                      -7-

                                   EXHIBIT A

                         LIST OF PRIOR INVENTIONS AND
                         ORIGINAL WORKS OF AUTHORSHIP


                                                            IDENTIFYING NUMBER
TITLE                           DATE                        OR BRIEF DESCRIPTION
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