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                                                                  EXHIBIT 10.16

                                SUMMIT DESIGN, INC.
                                EMPLOYMENT AGREEMENT

EMPLOYEE:           Sharon L. Beelart
EFFECTIVE DATE:     January 5, 1998

This Agreement is entered into as of the above date by and between SUMMIT 
DESIGN, INC., a Delaware corporation ("SUMMIT") and the above-named employee 
("Beelart").

1.   EMPLOYMENT AND DUTIES.  SUMMIT hereby employs Beelart to serve and 
perform in the role of Corporate Controller reporting to the Chief Financial 
Officer. Beelart agrees to perform the duties of this position to the best of 
her ability and to devote full time and attention to the transaction of 
SUMMIT's business.

2.   TERM AND TERMINATION.

     (a)  This Agreement shall have an initial term of four (4) years, unless 
sooner terminated in accordance with Subsection 2(b) and/or 2(c) and/or 2(d) 
below.  After the initial term of four (4) years, or any extension thereof, 
the term of the Agreement shall automatically extend for additional one (1) 
year period unless terminated by either party with at least thirty (30) days' 
advanced written notice prior to the end of the then-current term.  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)  In the event that Beelart notifies Summit of termination of her 
employment with Summit for any reason, this Agreement shall terminate as of 
the date of such notification.  Termination under this Section 2(b) is 
"Resignation".

     (c)  In the event that Summit notifies Beelart of termination of her 
employment by Summit because Beelart willfully abandoned the duties of her 
position or engaged in any business or criminal practice which the Chief 
Executive Officer reasonably determines is detrimental or harmful to the good 
name, goodwill, or reputation of Summit, or which does or could adversely 
effect the interests of Summit, then this Agreement shall terminate as of the 
date of such notification.  Termination under this Section 2(c) is "Cause".

     (d)  In the event that Summit notifies Beelart of termination of her 
employment by Summit for any reason other than specified in Section 2(b) 
and/or 2(c), this Agreement shall terminate as of the date of such 
notification. Termination under this Section 2(d) is "Convenience".

     (e)  Notwithstanding the above, termination of this Agreement shall not 
release Beelart from any obligations under Sections 4, 5, 6, and 7 hereof.

3.   COMPENSATION AND BENEFITS.  In consideration of the services to be 
performed by Beelart, SUMMIT agrees to pay Beelart the compensation and 
extend to Beelart the benefits consisting of the following:

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     (a)  Annual Base Salary of $84,000 paid twice monthly and prorated and
          beginning on the first pay period following the date agreed upon by
          Beelart and the Chief Financial Officer. 

     (b)  Monthly car allowance in accordance with Exexcutive Car Allowance
          program policy.

     (c)  Annual bonus of 25% under the terms of the Executive Bonus Plan.

     (d)  Equity:

          Summit has granted Beelart incentive stock options.  These shares are
          governed by the terms and conditions of the Summit Incentive Stock
          Options Plan ("ISO Plan").

          In addition, if more than 75% of the assets, or more than 50% of the
          outstanding shares of Summit are sold to another company, all of the
          shares granted to Beelart prior to the effective date of this
          agreement shall be 100% vested at closing of the transaction.

     (e)  Beelart shall be provided the right to participate in the health,
          dental, and life insurance programs provided for the employees of
          Summit.

     (f)  Beelart shall be granted three (3) weeks paid time off during each
          year of employment.  This paid time off shall be available for use
          according to the standard policy of Summit.

     (g)  In the event that this Agreement is terminated for Convenience as
          defined in Section 2(d), then Summit shall pay Beelart an amount per
          month equal to 1/12 of her Annual Base Salary at the time of
          termination plus all insurance benefits normally paid by Summit.  This
          payment shall continue monthly for nine (9) months provided, however,
          that if Beelart accepts full-time employment from another party prior
          to the end of such nine (9) months, these monthly payments shall
          immediately terminate.

4.   CONFIDENTIALITY.  Beelart acknowledges that certain customer lists, 
design work, and related information, equipment, computer software, and other 
proprietary products and information, whether of a technical or non-technical 
nature, including but not limited to schematics, drawings, models, 
photographs, sketches, blueprints, printouts, and program listings of SUMMIT, 
collectively referred to as "Technology", were and will be designated and 
developed by SUMMIT at great expense and over lengthy periods of time, are 
secret and confidential, are unique and constitute the exclusive property and 
trade secrets of SUMMIT, and any 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.  Beelart hereby agrees that he will not, at any time, 
without the express written consent of SUMMIT, publish, disclose, or divulge 
to any person, firm, or corporation any of the Technology, nor will Beelart 
use, directly or indirectly, for Beelart's own benefit or the 

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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 Beelart in connection with 
employment by SUMMIT shall belong exclusively to SUMMIT.

6.   RETURN OF DOCUMENTS.  Beelart 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 containing any 
confidential information of SUMMIT shall be the sole and exclusive property 
of SUMMIT, and shall be returned to SUMMIT upon the termination of employment 
for any reason whatsoever or upon the written request of SUMMIT.

7.   COMPLIANCE.  Beelart agrees to comply with all of SUMMIT's written 
employment policies, guidelines, and procedures as contained in an employment 
manual, including revisions and additions thereto.

8.   INJUNCTION.  In addition to all other legal rights and remedies, SUMMIT 
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 the State of Oregon. 
Unresolved disputes shall be resolved in a court of competent jurisdiction in 
Washington County, Oregon, 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 herein.  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:
                                       A Delaware Corporation


                                       /s/ Larry J. Gerhard
                                       -----------------------------------
                                       Larry J. Gerhard
                                       Chief Executive Officer, SUMMIT




"EMPLOYEE":                            BEELART:


                                       /s/ Sharon L. Beelart
                                       -----------------------------------
                                       Sharon L. Beelart







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