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                           SCHEDULE 14A INFORMATION

          Proxy Statement Pursuant to Section 14(a) of the Securities
                    Exchange Act of 1934 (Amendment No.  )
        
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                        Quickturn Design Systems, Inc.
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               (Name of Registrant as Specified In Its Charter)

                          
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   (Name of Person(s) Filing Proxy Statement, if other than the Registrant)

   
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CONTACTS:
     QUICKTURN DESIGN SYSTEMS, INC.               ABERNATHY MACGREGOR FRANK
       Joan Powell                                Pauline Yoshihashi
       Director, Marketing Communications         (213) 630-6550
       (408) 914-6701                             Matt Sherman
       joan@quickturn.com                         (212) 371-5999



FOR IMMEDIATE RELEASE


  QUICKTURN URGES STOCKHOLDERS NOT TO SUPPORT MENTORS GRAPHIC'S INADEQUATE BID

   MENTOR ADVISOR VALUED QUICKTURN AT MORE THAN $600 MILLION OR MORE THAN 
                                $30 PER SHARE


SAN JOSE, CALIF. (NOVEMBER 5, 1998) -- Quickturn Design Systems, Inc. (Nasdaq:
QKTN) announced today that it has mailed a letter to Quickturn stockholders from
Keith R. Lobo, president and chief executive officer of Quickturn, on behalf of
the Quickturn Board of Directors.  The Quickturn Board strongly urges
stockholders not to support Mentor Graphics Corporation's (Nasdaq: MENT) attempt
to take over Quickturn at what the Board believes is an opportunistic,
inadequate price. The complete text of the letter follows:

"November 4, 1998

Dear Fellow Quickturn Stockholder:

                 MENTOR IS TRYING TO BUY QUICKTURN ON THE CHEAP
                             --AND MENTOR KNOWS IT!

  We believe Mentor Graphics recognizes how well-positioned Quickturn is for
future growth, and that is exactly why Mentor has made a hostile bid for your
Company. However, MENTOR'S DESIRE TO BUY QUICKTURN AT A "BARGAIN PRICE" SHOULD
NOT COME AT THE EXPENSE OF YOU, QUICKTURN'S STOCKHOLDERS. Mentor has been urging
you and other stockholders to tender your shares into an offer that your Board
of Directors has determined is INADEQUATE AND NOT REFLECTIVE OF THE INHERENT
VALUE OF YOUR COMPANY.

  Your Board considered, among other things, the historical trading prices of
Quickturn's common stock, including the fact that MENTOR'S OFFER IS MORE THAN
                                                                    ---------
25% BELOW THE STOCK'S HIGHEST CLOSING PRICE OVER THE LAST YEAR, and less than 4%
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above its average closing price during the same period.

                 HERE'S WHAT MENTOR DOESN'T WANT YOU TO KNOW...

  What Mentor does not want you to know--and has fought in court/1/ to keep you
from hearing--is that ONE OF MENTOR'S OWN ADVISORS DETERMINED THAT QUICKTURN'S
                                                                   -----------
VALUE IS WELL IN EXCESS OF MENTOR'S CURRENT OFFER.
- ---------------------------------------------------

  The highly respected consulting firm, Arthur Andersen, in a confidential
report dated October 1997, said MENTOR'S PURCHASE OF QUICKTURN WOULD CREATE
INCREMENTAL VALUE TO MENTOR OF $610 MILLION TO $640 MILLION--THAT'S NEARLY THREE
                               ----------------------------                     
TIMES THE AMOUNT MENTOR IS CURRENTLY OFFERING FOR YOUR COMPANY.

                                    - more -

 
                                    - 2 -


               WHOSE INTERESTS WILL MENTOR'S NOMINEES REPRESENT?

  One of Mentor's own advisors believed Quickturn's value to be substantially
higher than the $12.125 per share offer currently on the table. Now Mentor is
attempting to seek your vote at a special stockholders meeting to gain control
of Quickturn by taking over your Board. Mentor is asking Quickturn stockholders
to remove your current Board of Directors--who were elected by you, as Quickturn
stockholders, in April of this year--and to replace them with Mentor's
handpicked slate of director nominees. Once in control, Mentor has said its
nominees intend to take all actions necessary to accept Mentor's bargain offer.
Mentor also is trying to induce you to vote for three self-serving proposals
submitted by Mentor. WE BELIEVE MENTOR'S NOMINEES WILL NOT REPRESENT THE BEST
INTERESTS OF QUICKTURN'S STOCKHOLDERS.

  YOUR BOARD CONTINUES TO CHALLENGE THE VALIDITY AND LEGALITY OF MENTOR'S
ATTEMPT TO CALL THE SPECIAL MEETING, and the ability to set the meeting and
record date of that special meeting. Subject to the resolution of litigation
between Quickturn and Mentor regarding these issues, QUICKTURN'S BOARD HAS SET
FRIDAY, JANUARY 8, 1999 AS THE DATE FOR THE SPECIAL STOCKHOLDER MEETING, in
accordance with Quickturn's bylaws.

  WE STRONGLY URGE YOU NOT TO VOTE THE MENTOR GOLD PROXY CARD AND NOT TO TENDER
YOUR SHARES TO THE INADEQUATE MENTOR OFFER.

  THE QUICKTURN BOARD HAS BEEN WORKING HARD ON BEHALF OF THE COMPANY AND ITS
STOCKHOLDERS. Your Board's rejection of Mentor's offer affirms its continued
confidence in Quickturn's future and its determination that stockholders should
be given every opportunity to participate fully in that future.

                    PARTICIPATE IN QUICKTURN'S BRIGHT FUTURE

             VOTE THE BLUE PROXY CARD AGAINST THE MENTOR PROPOSALS

  Your Board urges you to vote the enclosed BLUE proxy card today!

On Behalf of the Board of Directors,


/s/ Keith R. Lobo
Keith R. Lobo
Chief Executive Officer and President

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1  As part of the ongoing litigation between Mentor Graphics Corporation and
   Quickturn Design Systems, Mentor sought to block Quickturn from deposing
   Arthur Andersen and sought to prevent the introduction of the Arthur
   Andersen report at trial."



Quickturn Design Systems, Inc. is the leading provider of verification products
and time-to-market engineering (TtME(TM)) services for the design of complex ICs
and electronic systems. The company's products are used worldwide by developers
of high-performance computing, multimedia, graphics and communications systems.
Quickturn is headquartered at 55 W. Trimble Road, San Jose, CA 95131-1013;
Telephone: 408/914-6000. For more information, visit the Quickturn Web site at
www.quickturn.com or send e-mail to info@quickturn.com.

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