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                                                                   EXHIBIT 10.10

                              EMPLOYMENT AGREEMENT


                  Employee:  MOSHE GUY         ID. No. _______________

                  This Agreement is entered into as of February 25, 1999 by and
                  between Summit Design (EDA), Ltd., an Israeli corporation
                  (hereinafter "EDA"), a wholly owned subsidiary of Summit
                  Design, Inc., a Delaware corporation (hereinafter "Summit"),
                  and the above referenced employee (hereinafter "Guy ").

1.       EMPLOYMENT AND DUTIES:

         EDA hereby employs Guy to serve and perform for Summit and EDA in the
         role of President of EDA and Chief Technology Officer of Summit,
         reporting to the Chief Operating Officer or President or Chief
         Executive Officer of Summit. Guy agrees to perform the duties of this
         position to the best of his ability, and to devote full time and
         attention to the transaction of Summit's and EDA's business.

2.       TERM:

         (a)      This Agreement shall have a term of four (4) years, unless
                  sooner terminated in accordance with subsections 2(b) and/or
                  2(c) below. Both parties acknowledge that the employment
                  created herein is employment-at-will, and may be terminated
                  with or without cause under the terms stated herein.

         (b)      Notwithstanding the foregoing, this Agreement may be
                  immediately terminated by EDA in the event (i) that Guy
                  resigns or willfully abandons the duties of his position, (ii)
                  Guy engages or becomes engaged in any criminal or unethical
                  practice which the Board determines is detrimental or harmful
                  to the good name, goodwill, or reputation of Summit or EDA, or
                  which does or could adversely effect the interests of Summit
                  and EDA or (iii) of Guy's death or disability.

         (c)      In the event that this Agreement is terminated by EDA for any
                  reasons other than those specified in paragraph 2(b) or in the
                  event Summit and/or EDA has required (in writing) Guy to
                  perform in any role that does not include President of EDA
                  without Guy's consent (in writing), then

                  (i)      EDA shall pay Guy his then-current monthly Base
                           Salary plus the Fringe Benefits described in Sections
                           7(b)(i), (ii) and (iii), each for a total of fifteen
                           (15) months minus any amount and period provided for
                           by Managers Insurance (bituach menahalim) as defined
                           in Section 7(b). This total period is



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                           the ("Severance Period"). Notwithstanding the
                           foregoing, as a condition precedent to Guy receiving
                           these monthly payments and benefits, Guy must
                           execute the Settlement Agreement in the form
                           attached hereto as ANNEX A and the seven (7) day
                           revocation period referenced in Section 7 thereof
                           shall have expired.

                  (ii)     In addition, the unvested portion of the stock
                           option granted to Guy on February 25, 1999
                           exercisable for 100,000 shares of Summit's Common
                           Stock shall automatically accelerate and such
                           option shall be fully exercisable. Notwithstanding
                           the foregoing, if it is determined by Summit's
                           independent public accountants that the grant of
                           the option or the acceleration of the vesting of
                           the option would preclude accounting for a
                           transaction as a pooling of interests for
                           financial accounting purposes, the granting of the
                           option or this acceleration provision, as the case
                           may be, shall be null and void.

         (d)      It is agreed that in no way does the entering into this
                  Agreement cause a break in Guy's employment continuity at EDA
                  (the start date of which is as set forth in Guy's employment
                  agreement with EDA attached as Exhibit (A)), and until Guy is
                  no longer employed by EDA, his employment shall be considered
                  continuous under Israeli law.

3.       COMPENSATION:

         In consideration of the services to be performed by Guy, EDA agrees to
         pay Guy a base salary of 721,800 New Israeli Schekels per year ("Base
         Salary") and Fringe Benefits as defined in Section 7(b). EDA agrees to
         review Guy's Base Salary at least once a year.

         In addition, Guy shall receive the following:

         (a)      Annual bonus of up to 25% of Guy's Base Salary, as determined
                  by the terms of Summit's executive bonus plan to be adopted by
                  the Board.

         (b)      All cash compensation provided under this Agreement shall be
                  subject to usual withholding and payroll taxes as required by
                  Israeli law.

4.       CONFIDENTIALITY:

         Guy acknowledges that certain customer lists, design work and related
         information, equipment, computer software, and other proprietary
         products and information, whether of technical or non technical nature,
         including but not limited to schematics, drawings, models, photographs,
         sketches, blueprints, printouts, and program listing of Summit and its
         subsidiaries, collectively referred to as "Technology," were and will
         be designated and developed by Summit and its subsidiaries at great
         expense and over lengthy period of time, are secret and confidential,
         are unique and constitute the exclusive property and trade secrets of
         Summit and its subsidiaries, and the use or disclosure of such
         Technology, except in


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         accordance with and under the provisions of this or any other written
         agreements between the parties, would be wrongful and would cause
         irreparable injury to Summit and its subsidiaries.

         Guy therefore agrees that he will not, at any time, without the
         express written consent of Summit and its subsidiaries, publish,
         disclose or divulge to any person, firm or corporation any of the
         Technology, nor will Guy use, directly or indirectly, for Guy's own
         benefit or the benefit of any other person, firm or corporation, any
         of the Technology, except in accordance with this Agreement or other
         written agreements between the parties.

5.       INVENTIONS:

         All original written material including programs, charts, schematics,
         drawings, tables, tapes, listings and technical documentation which
         are prepared partially or solely by Guy in connection with employment
         by EDA, shall belong exclusively to EDA.

6.       RETURN OF DOCUMENTS:

         Guy acknowledges that all originals and copies of records, reports,
         documents, lists, plans, drawings, memoranda, notes, and other
         documentation related to the business of Summit or its subsidiaries or
         containing any confidential information of Summit or its subsidiaries
         shall be the sole and exclusive property of Summit or its
         subsidiaries, as appropriate, and shall be returned to Summit or its
         subsidiaries, as appropriate, upon the termination of employment for
         any reason whatsoever, or upon the written request of Summit or its
         subsidiaries.

7.       COMPLIANCE:

         (a)      Guy agrees to comply with all written employment policies,
                  guidelines and procedures of EDA, as contained in an
                  employment manual, including revisions and additions thereto.

         (b)      Exhibit (A) hereunder represents a previous employment
                  agreement between Guy and EDA. Paragraphs relating to
                  definitions of work hours, fringe benefits, conflict of
                  interests and non-competition are in force and are not being
                  canceled or modified by this agreement (excluding the
                  automatic release of the Managers Insurance as specified
                  hereunder).

         "Fringe Benefits" is defined as follows:

                  (i)      MANAGERS INSURANCE (BITUACH MENAHALIM): 5% pension
                           fund into "Managers Insurance" policy (Guy is
                           required to invest 5% into the same fund from his
                           monthly base salary); 8 1/3% severance fund into
                           "Managers Insurance" policy.

                           It is agreed that Guy will be entitled to all funds
                           (including earnings) accrued in the "Managers
                           Insurance" policy in any event that this Agreement
                           is


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                           terminated either by EDA or by Guy. The policy
                           belongs only to Guy and will automatically be
                           released to Guy once the employment agreement is
                           terminated without the need of a written release
                           letter from EDA.

                  (ii)     7.5% into Educational Fund (keren hishtalmut) (Guy
                           is required to contribute 2.5% into the same fund or
                           else this 7.5% are added to his base salary).

                  (iii)    A company car.

                  (iv)     Up to 30 days of sick leave per year (with doctor's
                           written approval).

                  (v)      22 vacation days per year, accrued up to 2 years (44
                           days).

                  (vi)     Annual recreational grant (Dmei Havra'a) as
                           specified in Exhibit (A).

8.       INJUNCTION:

         In addition to other legal rights and remedies, Summit and its
         subsidiaries shall be entitled to obtain from any court of competent
         jurisdiction preliminary and permanent injunctive relief of any actual
         or threatened violation of any term hereof without requirement of
         bond, as well as an equitable accounting of all profits or benefits
         arising out of such violation.

9.       WAIVER:

         The waiver of either party of a breach of any provision of this
         Agreement shall not operate or be construed as a waiver of any
         subsequent breach thereof.

10.      DISPUTES:

         The legal relations of the parties hereunder, and all other matters
         hereunder, shall be governed by the laws of Israel. Unresolved
         disputes shall be resolved in a court of competent jurisdiction in
         Israel, and all parties hereto consent to the jurisdiction of such
         court.

11.      ENTIRE AGREEMENT:

         This Agreement in conjunction with the paragraphs in the agreement
         attached as Exhibit A specifically referred to herein constitute the
         entire agreement between the parties hereto, and fully supersede any
         and all prior agreements or understandings, written or oral, between
         the parties hereto pertaining to the subject matter hereof. Without
         limiting the generality of the foregoing, the employment agreement
         dated as of July 1, 1997 between EDA and Guy is superseded in all
         respects by this Agreement. No modification of amendment hereof is
         effective unless in writing and signed by both parties.


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         In WITNESS WHEREOF, the parties have executed this Agreement as of the
date first herein above written.

         "EMPLOYER:         Summit Design (EDA), Ltd. an Israel Corporation


                            By:   _____________________________________________

                                  Name: _______________________________________

                                  Title:_______________________________________


                            By:   _____________________________________________

                                  Name: _______________________________________

                                  Title:_______________________________________



      "EMPLOYEE":           ___________________________________________________

                                     Moshe Guy


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