AMENDED & RESTATED SEVERANCE AGREEMENT, COHEN


 EXHIBIT 10.5

 AMENDED AND RESTATED AGREEMENT

      This Agreement is entered
   into as of this 10th day of February, 2000, between Parametric Technology
   Corporation, a Massachusetts corporation (the "Company"), and
   Barry F. Cohen (the "Officer"), and amends and restates the
   Agreement dated February 1, 1998 between the Company and the
   Officer.

      WHEREAS, the Officer is
   the Executive Vice President, Marketing; and

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

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

      1.     
   Termination Notice. The Company agrees that it may not terminate the
   employment of the Officer unless (i) such termination is for Cause (as
   defined below) or (ii) the Company has delivered to the Officer a written
   notice of such termination (the "Termination Notice") at least six
   months in advance of the termination date. The duties of the Officer 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
   Termination Notice (the "Notice Date") until the earlier of (i)
   the date six months after the Notice Date or (ii) the date the Officer
   commences employment with another company or organization, the Company shall
   pay to the Officer a salary that is equal, on an annualized basis, to the
   highest annual salary (excluding any bonuses) in effect with respect to the
   Officer during the six-month period immediately preceding the Termination
   Notice.

      3.     
   Stock Options. Effective upon a Change in Control (as defined below)
   of the Company, all stock options granted to the Officer 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 the Officer hereby agree that such option agreements are
   hereby and will be deemed amended to give effect to this
   provision.

      4.     
   Definitions. 

           
        (a)      A
   termination by the Company of the Officer's employment for "Cause"
   shall mean termination (i) for the Officer's willful and continued failure
   to substantially perform his duties to the Company (other than any such
   failure resulting from the Officer's incapacity due to physical or mental
   illness or any such actual or perceived failure after a Change in Status of
   the Officer), provided that (a) the Company has delivered a written demand
   for substantial performance to the Officer specifically identifying the
   manner in which the Company believes that

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 the Officer has not substantially performed his duties, and (b) the Officer
   has not cured such failure within 30 days after such demand, (ii) for
   willful conduct by the Officer which is demonstrably and materially
   injurious to the Company, or (iii) for the Officer's willful violation of
   any material provision of any confidentiality, nondisclosure, assignment of
   invention, noncompetition or similar agreement entered into by the Officer
   in connection with his employment by the Company. For purposes of this
   paragraph, no act or failure to act on the Officer's part shall be deemed
   "willful" unless done or omitted to be done by the Officer 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 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.

      5.     
   Term. This Agreement shall continue in effect until February 28,
   2003, unless extended by the mutual written consent of the Company and the
   Officer.

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      6.     
   Successors.

           
        (a)      This
   Agreement is personal to the Officer and without the prior written consent
   of the Company shall not be assignable by the Officer 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 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.

           
        (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:

           
        Parametric Technology Corporation
 

           
        128 Technology Drive
 

           
        Waltham, MA 02453
 

           
        Attention: Corporate Counsel

           
        If to the Officer:

           
        Barry F. Cohen
 


              
       649 Sudbury Road
 


              
       Concord, MA 01742

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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/ Barry F. Cohen
	 	 	 
 
	 	 	Barry F. Cohen 


  

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