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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Notes:


 
 
                                              November 19, 1998
 
Dear Fellow Quickturn Stockholder:
 
         DON'T TENDER YOUR SHARES! DON'T VOTE MENTOR'S GOLD PROXY CARD!
 
                    VOTE QUICKTURN'S BLUE PROXY CARD TODAY!
 
Let's set the record straight.
 
We've said all along that we believe Mentor's offer is inadequate and doesn't
reflect the inherent value of Quickturn. Here's why:
 
 . OUR BUSINESS IS GREAT -- In the third quarter of 1998, Quickturn exceeded
  consensus analysts' estimates. Net income in the third quarter was $735,000
  or $0.04 per share compared to consensus analysts' estimates of a loss of
  $0.03 per share./1/ During the third quarter, we witnessed the resurgence of
  customer orders in design and verification. And that trend is continuing well
  into the fourth quarter. One of the major factors that will drive the future
  marketplace for Quickturn's verification products is denser and more complex
  chip designs. Design activities are growing at a faster pace than ever
  before, and we are confident that our customers will begin even more projects
  during 1999.
 
 . QUICKTURN HAS THE LARGEST BACKLOG POSITION WE'VE EVER SEEN -- As we entered
  the fourth quarter of 1998, we had the strongest backlog so far this year.
  During the fourth quarter, our backlog position has increased to the largest
  Quickturn has ever had, partially due to a $12 million customer order from a
  large Japanese electronics company for our premier emulation technology and
  design services.
 
 . OUR NEW PRODUCTS ARE COMING TO MARKET -- Our recently announced CoBALT Plus
  product features the industry's highest capacity available in a single
  chassis. It represents a major enhancement to CoBALT(TM), which in itself was
  a quantum leap in capacity and compilation speed for emulation, setting
  levels that have yet to be reached by any other emulation supplier. As CoBALT
  Plus, our breakthrough Mercury(TM) product and the enhancements to our
  SpeedSim(TM) product reach full production by the end of 1998, we believe
  that this will translate into significant near- to mid-term value for our
  stockholders.
 
 . WE BELIEVE QUICKTURN WILL GENERATE SIGNIFICANT VALUE FOR OUR STOCKHOLDERS IN
  THE NEAR-, MID- AND LONG-TERM -- We have the patents, we have the technology,
  we have the customer base, we have the R&D and we have the people. Quickturn
  continues to beat Mentor in the marketplace and we're beating them in the
  courts.
 
 
- --------
1 Excluding the legal and advisory expenses of approximately $4.0 million, or
  $0.13 per share, net of tax, related to Quickturn's defense against Mentor's
  attempted hostile takeover.

 
Your board continues to believe that the value of Quickturn is well in excess
of Mentor's low-ball offer. In fact, Mentor's offer is more than 25% below the
stock's highest closing price over the last year, and less than 4% above its
average closing price during the same period.
 
In fact, ONE OF MENTOR'S OWN ADVISORS DETERMINED THAT QUICKTURN'S VALUE IS
SUBSTANTIALLY HIGHER THAN 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.
 
WE STRONGLY URGE YOU NOT TO TENDER YOUR SHARES TO MENTOR'S INADEQUATE OFFER AND
NOT TO VOTE MENTOR'S GOLD PROXY CARD.
 
The Quickturn Board has been working hard on behalf of the company and its
stockholders. Your Board's rejection of Mentor's offer is based on 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 TODAY!
 
On Behalf of the Board of Directors,
Keith R. Lobo
Chief Executive Officer and President
 
 
                                   IMPORTANT
 
 1. REGARDLESS OF HOW MANY SHARES YOU OWN, YOUR VOTE IS VERY IMPORTANT. PLEASE
    SIGN, DATE AND MAIL THE ENCLOSED BLUE PROXY CARD. PLEASE VOTE EACH BLUE
    PROXY CARD YOU RECEIVE SINCE EACH ACCOUNT IN WHICH YOU OWN SHARES MUST BE
    VOTED SEPARATELY. ONLY YOUR LATEST DATED PROXY CARD COUNTS.
 
 2. WE URGE YOU NOT TO RETURN ANY GOLD PROXY CARD SENT TO YOU BY MENTOR.
 
 3. IF YOUR SHARES ARE HELD IN THE NAME OF A BANK, BROKER OR OTHER NOMINEE,
    PLEASE DIRECT THE PARTY RESPONSIBLE FOR YOUR ACCOUNT TO VOTE THE BLUE
    PROXY CARD AS RECOMMENDED BY THE BOARD OF DIRECTORS.
 
  IF YOU HAVE ANY QUESTIONS on how to vote your shares, please call our proxy
                                   solicitor:
                     Morrow & Co., Inc. at (800) 662-5200.