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                                QUICKTURN DESIGN SYSTEMS, INC.
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                (Name of Registrant as Specified In Its Charter)

                                 MENTOR GRAPHICS CORPORATION
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               MENTOR GRAPHICS SAYS SPECIAL MEETING OF QUICKTURN
               STOCKHOLDERS CONVENED AND ADJOURNED TO NOVEMBER 24

         -- QUICKTURN STOCKHOLDERS URGED TO TENDER SHARES ON OR BEFORE
                         OCTOBER 30 EXPIRATION DATE --

WILSONVILLE, OR, OCTOBER 29, 1998 -- Mentor Graphics Corporation (Nasdaq: 
MENT) announced that, pursuant to an agreement with Quickturn Design Systems, 
Inc. (Nasdaq: QKTN), the special meeting of Quickturn stockholders called by 
Mentor Graphics convened today and was immediately adjourned until November 
24, 1998 without conducting any substantive business.  The record date for 
the November 24, 1998 special meeting called by Mentor continues to be 
September 10, 1998.

As previously announced, the principal purpose of the special meeting is to 
vote on replacing the current members of the Quickturn Board of Directors 
with a slate of independent directors nominated by Mentor Graphics.  If the 
nominees are elected, Mentor Graphics expects that, subject to their 
fiduciary duties to all Quickturn stockholders, the new directors will take 
the steps necessary to facilitate the stockholders' ability to accept Mentor 
Graphics' $12.125 per share all-cash offer.  Quickturn continues to assert, 
nevertheless, that the special meeting date has been conditionally set for 
January 8, 1999, citing a bylaw that it purported to adopt after Mentor 
Graphics' offer commenced on August 12, 1998.

Dr. Walden C. Rhines, President and Chief Executive Officer of Mentor 
Graphics, said:  "We look forward to the November 24 special meeting, and in 
the meantime urge Quickturn stockholders to tender their shares before the 
expiration of Mentor's Offer at 12:00 Midnight, New York City time, on 
Friday, October 30, 1998, unless extended.  Tendering shares is the best way 
for Quickturn stockholders to send a message to the Quickturn Board of 
Directors to end their entrenchment tactics."

Separately, the trial in which Mentor Graphics challenged the validity of the 




bylaw and poison pill amendments adopted by Quickturn after Mentor Graphics 
commenced its $12.125 per share all-cash offer on August 12, 1998, ended 
Wednesday afternoon in Delaware Court of Chancery.  Mentor Graphics expects 
that post-trial briefs from both sides will be completed by November 6, 1998, 
and a decision by the Court of Chancery is expected shortly thereafter.

Mentor Graphics' Offer to Purchase and ancillary documents are available on a 
Mentor Graphics World Wide Web site at http://www.mentorg.com/file.

The Dealer Manager for the Offer is Salomon Smith Barney.  The Information 
Agent for the Offer is MacKenzie Partners, Inc., which can be reached 
toll-free at 800-322-2885 or by collect call at 212-929-5500.

     CONTACT:   Anne M. Wagner                 Roy Winnick/Todd Fogarty
                Vice President, Marketing      Kekst and Company
                503/685-1462                   212/521-4800


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