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                                                                  EXHIBIT 10.10

                              EMPLOYMENT AGREEMENT


        EMPLOYEE:        MOSHE GUY
                         --------------------------

        This Agreement is entered into as of July 1, 1997 (hereinafter "Starting
        Day"). 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"), pursuant to the Employment Agreement
        between EDA and Moshe Guy.


1.   EMPLOYMENT AND DUTIES:

EDA hereby employs Guy to serve and perform for Summit and EDA in the role of
Vice President of Israel Operations for Summit Design, Inc. or President,
Summit Design (EDA) Ltd., reporting to the President and Chief Executive
Officer, or Chief Operating Officer, 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 an initial term of four (4) years, unless
          sooner terminated in accordance with Section 2(b) and (c) below.
          After the initial term of four years, or any extension term, the
          term of Agreement shall be automatically extended for additional
          one-year terms unless terminated by either party with at least 90
          days advance written notice (the "Notice") prior to the end of the
          then current term. Without limiting the provisions of Section 2(b)-
          (d) 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 that Guy resigns or willfully
          abandons the duties of his position or 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.

     (c)  In the event that this Agreement is terminated for any reasons
          other than those specified in paragraph 2(b) or in the event Summit
          and/or EDA requires Guy to perform in any role other than as
          described in Section 1 above without Guy's consent, then EDA shall
          pay Guy his monthly Base Salary plus all current benefits, each for
          a total of twelve (12 ) months minus any amount and period provided
          for by Managers Insurance (bituach menahalim) as defined in section
          7(b). This total period is the ("Severance Period"). During the
          Severance Period, Guy will be considered an EDA employee, and will
          not have to perform any active task or active duty for EDA in order
          to maintain the payments and benefits mentioned in this subsection
          (c). However, if Guy accepts full-time employment


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          or consulting from another party prior to the expiration of the
          Severance Period, all payment and benefits under this subsection
          (c) shall immediately terminate.

     (d)  It is agreed that in no way does the entering into this Employment
          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 Four hundred sixty two thousand eight hundred New
Israeli Schekels (NIS462,800) per year ("Base Salary") and Fringe Benefits.
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 the Base Salary, as determined by the
          terms of the Summit Executive Bonus Plan.

     (b)  Compensation for each additional one year period for which Guy's
          employment is extended under Section 2 shall be fixed within 60
          days of the expiration of the preceding one year period that this
          Agreement is in effect.

     (c)  All cash compensation provided under this Agreement shall be
          subject to usual withholdings 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,
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
at "Technology", were and will be designated and developed by Summit 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
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.


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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 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, 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 the 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:

               MANAGER'S 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 the employment agreement is 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.

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

               A company car.


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               Up to thirty (30) days of Sick Leave per year (with a doctor's
               written approval).

               Twenty two (22) Vacation days per year, with an accrual cap of
               two (2) years or forty four (44) days.

               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 by either part 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 disputed 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 sets forth the entire Agreement between the parties hereto,
and fully supersedes any and all prior Agreements or understandings, written
or oral, between the parties hereto pertaining to the subject matter hereof.
No modification of amendment 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:  /s/ LARRY J. GERHARD
                                         ---------------------------
                                         Larry J. Gerhard
                                         President

"EMPLOYEE":                         By:  /s/ MOSHE GUY
                                         ---------------------------
                                         Moshe Guy

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