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                                                                   EXHIBIT 10.11
                                   Agreement
                                   ---------

     This Agreement is entered into as of this 29th day of October, 1998,
between Parametric Technology Corporation, a Massachusetts corporation (the
"Company"), and Paul J. Cunningham ("Cunningham").

     WHEREAS, Cunningham is the Executive Vice President, Sales - Primary
Accounts; and

     WHEREAS, to provide incentive for Cunningham to maintain employment with
the Company, the Company desires to make the following arrangements with
Cunningham concerning his termination of employment.

     NOW, THEREFORE, the Company and Cunningham hereby agree as follows:

     1.   Termination Notice.  The Company agrees that it may not terminate the
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employment of Cunningham unless (i) such termination is for Cause (as defined
below) or (ii) the Company has delivered to Cunningham a written notice of such
termination (the "Termination Notice") at least six months in advance of the
termination date.  The duties of Cunningham during the period from the date of
delivery of a Termination Notice until the termination of his employment shall
be as determined by the Board of Directors.

     2.   Salary.   During the period from the date of delivery of the
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Termination Notice (the "Notice Date") until the earlier of (i) the date six
months after the Notice Date or (ii) the date Cunningham commences employment
with another company or organization, the Company shall pay to Cunningham a
salary that is equal, on an annualized basis, to the highest annual salary
(excluding any bonuses) in effect with respect to Cunningham during the six-
month period immediately preceding the Termination Notice.

     3.   Stock Options.      Effective upon a Change in Control (as defined
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below) of the Company, all stock options granted to Cunningham and then
outstanding under any Stock Option Plan (as defined below) of the Company shall
become exercisable in full, notwithstanding any vesting schedule or other
provisions to the contrary in the agreements evidencing such options; and the
Company and Cunningham hereby agree that such option agreements are hereby and
will be deemed amended to give effect to this provision.
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     4.   Definitions.
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          (a)  A termination by the Company of Cunningham's employment for
"Cause" shall mean termination (i) for Cunningham's willful and continued
failure to substantially perform his duties to the Company (other than any such
failure resulting from Cunningham's incapacity due to physical or mental illness
or any such actual or perceived failure after a Change in Status of Cunningham),
provided that (a) the Company has delivered a written demand for substantial
performance to Cunningham specifically identifying the manner in which the
Company believes that Cunningham has not substantially performed his duties, and
(b) Cunningham has not cured such failure within 30 days after such demand, (ii)
for willful conduct by Cunningham which is demonstrably and materially injurious
to the Company, or (iii) for Cunningham's willful violation of any material
provision of any confidentiality, nondisclosure, assignment of invention,
noncompetition or similar agreement entered into by Cunningham in connection
with his employment by the Company.  For purposes of this paragraph, no act or
failure to act on Cunningham's part shall be deemed "willful" unless done or
omitted to be done by Cunningham not in good faith and without reasonable belief
that his action or omission was in the best interests of the Company.
          (b)  A "Change in Control" of the Company shall mean the occurrence of
any of the following events: (i) any "person", as such term is used in Sections
13(d) and 14(d) of the Securities Exchange Act of 1934, as amended (the
"Exchange Act") (other than the Company, any trustee or other fiduciary holding
securities under an employee benefit plan of the Company, or any corporation
owned directly or indirectly by the stockholders of the Company in substantially
the same proportion as their ownership of stock in the Company) is or becomes
the "beneficial owner" (as defined in Rule 13d-3 under the Exchange Act),
directly or indirectly, of securities of the Company representing 50% or more of
the combined voting power of the Company's then outstanding securities (other
than as a result of acquisitions of such securities from the Company); (ii)
individuals who, as of the date hereof, constitute the Board of Directors of the
Company (the "Incumbent Board") cease for any reason to constitute at least a
majority of the Board, provided that any person becoming a director subsequent
to the date hereof whose election, or nomination for election by the Company's
stockholders, was approved by a vote of at least a majority of the directors
then comprising the Incumbent Board (other than an election or nomination of an
individual

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whose initial assumption of office is in connection with an actual or threatened
election contest relating to the election of the directors of the Company) shall
be, for purposes of this Agreement, considered to be a member of the Incumbent
Board; (iii) the stockholders of the Company approve a merger or consolidation
of the Company with any other corporation, other than (A) a merger or
consolidation which would result in the voting securities of the Company
outstanding immediately prior thereto continuing to represent (either by
remaining outstanding or by being converted into voting securities of the
surviving entity) more than 50% of the combined voting power of the voting
securities of the Company or such surviving entity outstanding immediately after
such merger or consolidation or (B) a merger or consolidation effected to
implement a recapitalization of the Company (or similar transaction) in which no
"person" (as defined above) acquires more than 20% of the combined voting power
of the Company's then outstanding securities; or (iv) the stockholders of the
Company approve a plan of complete liquidation of the Company or an agreement
for the sale or disposition by the Company of all or substantially all of the
Company's assets.

(c)  A "Stock Option Plan" of the Company shall mean any stock option or equity
compensation plan of the Company in effect at any time, including without
limitation the 1987 Incentive Stock Option Plan, the 1997 Incentive Stock Option
Plan 1997 and the 1997 Non-statutory Stock Option Plan.

     5.   Term.    This Agreement shall continue in effect until October 1,
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2001, unless extended by the mutual written consent of the Company and
Cunningham.

     6.   Successors.
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          (a)  This Agreement is personal to Cunningham and without the prior
written consent of the Company shall not be assignable by Cunningham otherwise
than by will or the laws of descent and distribution.

          (b)  This Agreement shall inure to the benefit of and be binding upon
the Company and its successors and assigns.

          (c)  The Company will require any successor (whether direct or
indirect, by purchase, merger, consolidation or otherwise) to all or
substantially all of the business and/or assets of the Company to assume
expressly and agree to perform this Agreement in the same manner and to the same
extent that the

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Company would be required to perform it if no such succession had taken place.
As used in this Agreement, "Company" shall mean the Company as defined above and
any successor to its business and/or assets as aforesaid which assumes and
agrees to perform this Agreement.

     7.   Miscellaneous.
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          (a)  This Agreement shall be governed by and construed in accordance
with the laws of the Commonwealth of Massachusetts, without reference to
principles of conflict of laws.

          (b)  This Agreement may not be amended or modified otherwise than by a
written agreement executed by the parties hereto or their respective successors
and legal representatives.

          (c)  All notices and other communications hereunder shall be in
writing and shall be delivered by hand delivery, by a reputable overnight
courier service, or by registered or certified mail, return receipt requested,
postage prepaid, in each case addressed as follows:

     If to the Company:
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     Parametric Technology Corporation
     128 Technology Drive
     Waltham, MA 02453
     Attention: Vice President - General Counsel

     If to Cunningham:
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     Paul Cunningham
     73 Marlboro Street, #6
     Boston, MA 02116

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or to such other address as either party shall have furnished to the other in
writing in accordance herewith. Any notice or communication shall be deemed to
be delivered upon the date of hand delivery, one day following delivery to such
overnight courier service, or three days following mailing by registered or
certified mail.

     EXECUTED as of the date first written above.

                           PARAMETRIC TECHNOLOGY CORPORATION

                           By: /s/ C. Richard Harrison
                               ------------------------
                               C. Richard Harrison
                               President and Chief Operating Officer

                               /s/ Paul J. Cunningham
                               -----------------------
                               Paul J. Cunningham

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