Exhibit 10.1

AMENDMENT TO EMPLOYMENT AGREEMENT

     This Amendment to Employment Agreement (this “First Amendment”) is made and
entered into as of the 17th day of May, 2005, by and between Cadence Design
Systems, Inc. (“Cadence”) and Michael J. Fister (“Executive”).

W I T N E S S E T H:

     WHEREAS, Cadence and Executive have entered into that certain Employment
Agreement effective May 12, 2004 (the “Agreement”); and

     WHEREAS, Cadence and Executive desire to amend the Agreement as more
particularly set forth herein.

     NOW, THEREFORE, for and in consideration of the premises, the mutual
covenants and agreements herein set forth, and for other good and valuable
consideration, the receipt, adequacy and sufficiency of which are hereby
expressly acknowledged by the parties hereto, the parties hereto do hereby
covenant and agree as follows:

     1. Relocation Benefits. Effective May 15, 2005, Section 3(c) of the
Agreement shall be deleted in its entirety, and inserted in lieu thereof shall
be the following:

     (c) The Company shall provide Executive with (i) a housing allowance of
$5,000 per month from May 12, 2004 through May 15, 2005, (ii) a housing
allowance of $17,000 per month from May 16, 2005 through May 15, 2007, and
(iii) reimbursement of such other reasonable and actual relocation expenses
incurred by Executive as may be agreed to by the Company.

 

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     2. Ratification. The Agreement, as modified by this Amendment, is hereby
ratified and confirmed by Cadence and Executive.

     IN WITNESS WHEREOF, the undersigned have caused this Amendment to be
executed and delivered as of the date first above written.

          CADENCE DESIGN SYSTEMS, INC.    
 
       
By:
  /s/ R.L. Smith McKeithen   /s/ Michael J. Fister

       

  Name: R.L. Smith McKeithen   Michael J. Fister

  Title: Senior Vice President & General Counsel    

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