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                        QUICKTURN DESIGN SYSTEMS, INC.
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               (Name of Registrant as Specified in Its Charter)
 
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                                                                     EXHIBIT 72
 
CONTACTS:
 
QUICKTURN DESIGN SYSTEMS, INC.                      ABERNATHY MACGREGOR FRANK
Ray Ostby                                           Pauline Yoshihashi
(408) 914-6000                                      (213) 630-6550
                                                    Matt Sherman
                                                    (212) 371-5999
 
FOR IMMEDIATE RELEASE
 
       QUICKTURN'S BOARD REJECTS MENTOR'S JANUARY 6 REVISED UNSOLICITED
              PROPOSAL TO ACQUIRE 2.1 MILLION SHARES OF QUICKTURN
 
  MENTOR'S PURPORTED SECOND-STEP MERGER PROPOSAL CONDITIONS INCLUDE SECURING
                                   FINANCING
 
         QUICKTURN REMAINS COMMITTED TO STRATEGIC MERGER WITH CADENCE
 
  SAN JOSE, Calif., January 7, 1999--Quickturn Design Systems, Inc. (Nasdaq:
QKTN) announced today that its Board of Directors rejected the January 6, 1999
revised unsolicited proposal by Mentor Graphics Corporation (Nasdaq: MENT) to
acquire 2,100,000 shares of Quickturn. The Quickturn Board continues to
strongly recommend that stockholders not tender their shares to Mentor's
partial tender offer, and urges Quickturn stockholders who may have tendered
to withdraw their shares.
 
  In rejecting Mentor's revised partial tender offer, the Quickturn Board
considered, among other things, that Mentor's revised bid is not an offer for
all of Quickturn's outstanding shares, but rather is limited to an offer to
purchase 2,100,000 shares, or about 11.6%, of Quickturn. The Board also
considered the fact that Mentor's purported proposal for a second-step merger
is highly conditional and, among other things, is subject to Mentor's securing
necessary financing. Mentor's second-step merger proposal also is conditioned
on Mentor's ability to conduct due diligence, its negotiation of a merger
agreement with Quickturn, and other unspecified conditions. The Quickturn
Board also believes that Mentor's proposal could interfere with Quickturn's
definitive merger agreement with Cadence Design Systems, Inc. (NYSE: CDN),
which the Board reaffirmed is in the best interests of Quickturn and its
stockholders.
 
  As previously announced on January 5, 1999, Cadence and Quickturn amended
their merger agreement to increase to $15 from $14 the amount of Cadence stock
that Quickturn stockholders will receive for each Quickturn share they own.
Under terms of the Cadence-Quickturn merger agreement, Cadence will acquire
Quickturn in a tax-free, stock-for-stock transaction with an aggregate
purchase price of approximately $271 million for all of the outstanding shares
of Quickturn.
 
  Keith R. Lobo, president and chief executive officer of Quickturn, said,
"Quickturn's Board has accepted an offer from Cadence for 100% of Quickturn
that involves no financing issues, provides all Quickturn stockholders with
significant value for their shares, and allows them to participate in the
long-term benefits inherent in this strategic combination. In contrast,
Mentor's most recent proposal is not a real offer to purchase the entire
company, and Mentor has even stated that it does not have committed financing
for such a proposal. Mentor's latest proposal also imposes new conditions that
make its consummation even more uncertain. Further, as Mentor is well aware,
its proposal continues to impose conditions that violate the Cadence-Quickturn
merger agreement.
 

 
  "Mentor is simply trying to gain control of Quickturn through the back
door," added Mr. Lobo. "Our merger agreement with Cadence will be imperiled if
our stockholders vote to replace Quickturn's current directors with Mentor's
nominees. Cadence has noted that it will constitute a breach of the Cadence-
Quickturn merger agreement if Quickturn is forced to share confidential
information with Mentor--an expressed condition of Mentor's proposal.
Additionally, under certain circumstances, Mentor may be in a position to
block any pooling-of-interests transaction, including the Cadence merger.
Cadence has stressed that it will not proceed with the merger if pooling-of-
interests treatment is not available, thereby denying the benefits of the
transaction for all Quickturn stockholders. Put simply, the Quickturn Board
believes that our merger agreement with Cadence is the best way to deliver
superior value for 100% of Quickturn's outstanding shares."
 
  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.