EXHIBIT 3.1
                                    RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                                  ANSYS, INC.

     ANSYS, Inc., a corporation organized and existing under the laws of the
State of Delaware (the "Corporation"), hereby certifies as follows:

     1.  The name of the Corporation is ANSYS, Inc.  The date of the filing of
its original Certificate of Incorporation with the Secretary of State of the
State of Delaware was January 12, 1994.  The name under which the Corporation
filed its original Certificate of Incorporation was SAS Holdings, Inc.

     2.  This Restated Certificate of Incorporation only restates and integrates
and does not further amend the provisions of the Third Amended and Restated
Certificate of Incorporation of the Corporation filed with the Secretary of
State of the State of Delaware on June 20, 1996 (the "Third Amended and Restated
Certificate of Incorporation"), there is no discrepancy between the provisions
of this Restated Certificate of Incorporation and the provisions of the Third
Amended and Restated Certificate of Incorporation, and was duly adopted by the
Board of Directors in accordance with the provisions of Section 245 of the
General Corporation Law of the State of Delaware (the "DGCL").

     3.  The text of the Third Amended and Restated Certificate of Incorporation
is hereby restated in its entirety to provide as herein set forth in full.


                                   ARTICLE I

                                      NAME
                                      ----

     The name of the Corporation is ANSYS, Inc.

 
                                  ARTICLE II

                               REGISTERED OFFICE
                               -----------------

          The address of the registered office of the Corporation in the State
of Delaware is 1209 Orange Street, in the City of Wilmington, County of New
Castle.  The name of its registered agent at such address is The Corporation
Trust Company.


                                  ARTICLE III

                                   PURPOSES
                                   --------

          The nature of the business or purposes to be conducted or promoted by
the Corporation is to engage in any lawful act or activity for which
corporations may be organized under the DGCL.


                                  ARTICLE IV

                                 CAPITAL STOCK
                                 -------------

          Section 1. Number of Shares.
          --------------------------- 

          The total number of shares of capital stock which the Corporation
shall have the authority to issue is Fifty-Two Million (52,000,000) shares, of
which (i) Two Million (2,000,000) shares shall be Undesignated Preferred Stock,
par value $.01 per share (the "Preferred Stock"), and (ii) Fifty Million
(50,000,000) shares shall be Common Stock, par value $.01 per share (the "Common
Stock").  As set forth in this Article IV, the Board of Directors or any
authorized committee thereof is authorized from time to time to establish and
designate one or more series of Preferred Stock, to fix and determine the
variations in the relative rights and preferences as between the different
series of Preferred Stock in the manner hereinafter set forth in this Article
IV, and to fix or alter the number of shares comprising any such series and the
designation thereof to the extent permitted by law.

          The number of authorized shares of the class of Preferred Stock may be
increased or decreased (but not below the number of shares outstanding) by the
affirmative vote of the holders of a majority of the Common Stock, without a
vote of the holders of the Preferred Stock, pursuant to the resolution or
resolutions establishing the class of Preferred Stock or this Restated
Certificate of Incorporation, as it may be amended from time to time.

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          Section 2. General.
          ------------------ 

          The designations, powers, preferences and rights of, and the
qualifications, limitations and restrictions upon, each class or series of stock
shall be determined in accordance with, or as set forth below in, Sections 3 and
4 of this Article IV.

          Section 3. Common Stock.
          ----------------------- 

          Subject to all of the rights, powers and preferences of the Preferred
Stock, and except as provided by law or in this Article IV (or in any
certificate of designation of any series of Preferred Stock) or by the Board of
Directors or any authorized committee thereof pursuant to this Article IV:

          (a) the holders of the Common Stock shall have the exclusive right to
vote for the election of Directors and on all other matters requiring
stockholder action, each share being entitled to one vote;

          (b) dividends may be declared and paid or set apart for payment upon
the Common Stock out of any assets or funds of the Corporation legally available
for the payment of dividends, but only when and as declared by the Board of
Directors or any authorized committee thereof; and

          (c) upon the voluntary or involuntary liquidation, dissolution or
winding up of the Corporation, the net assets of the Corporation shall be
distributed pro rata to the holders of the Common Stock in accordance with their
respective rights and interests.

          Section 4. Preferred Stock.
          -------------------------- 

          Subject to any limitations prescribed by law, the Board of Directors
or any authorized committee thereof is expressly authorized to provide for the
issuance of the shares of Preferred Stock in one or more series of such stock,
and by filing a certificate pursuant to applicable law of the State of Delaware,
to establish or change from time to time the number of shares to be included in
each such series, and to fix the designations, powers, preferences and the
relative, participating, optional or other special rights of the shares of each
series and any qualifications, limitations and restrictions thereof.  Any action
by the Board of Directors or any authorized committee thereof under this Section
4 shall require the affirmative vote of a majority of the Directors then in
office or a majority of the members of such committee.  The Board of Directors
or any authorized committee thereof shall have the right to determine or fix one
or more of the following with respect to each series of Preferred Stock to the
extent permitted by law:


          (a) The distinctive serial designation and the number of shares 
constituting such series;

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          (b) The dividend rates or the amount of dividends to be paid on the
shares of such series, whether dividends shall be cumulative and, if so, from
which date or dates, the payment date or dates for dividends, and the
participating and other rights, if any, with respect to dividends;

          (c) The voting powers, full or limited, if any, of the shares of 
such series;

          (d) Whether the shares of such series shall be redeemable and, if so,
the price or prices at which, and the terms and conditions on which, such shares
may be redeemed;

          (e) The amount or amounts payable upon the shares of such series and
any preferences applicable thereto in the event of voluntary or involuntary
liquidation, dissolution or winding up of the Corporation;

          (f) Whether the shares of such series shall be entitled to the benefit
of a sinking or retirement fund to be applied to the purchase or redemption of
such shares, and if so entitled, the amount of such fund and the manner of its
application, including the price or prices at which such shares may be redeemed
or purchased through the application of such fund;

          (g) Whether the shares of such series shall be convertible into, or
exchangeable for, shares of any other class or classes or of any other series of
the same or any other class or classes of stock of the Corporation and, if so
convertible or exchangeable, the conversion price or prices, or the rate or
rates of exchange, and the adjustments thereof, if any, at which such conversion
or exchange may be made, and any other terms and conditions of such conversion
or exchange;

          (h) The price or other consideration for which the shares of such 
series shall be issued;

          (i) Whether the shares of such series which are redeemed or converted
shall have the status of authorized but unissued shares of Preferred Stock (or
series thereof) and whether such shares may be reissued as shares of the same or
any other class or series of stock; and

          (j) Such other powers, preferences, rights, qualifications,
limitations and restrictions thereof as the Board of Directors or any authorized
committee thereof may deem advisable.

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                                   ARTICLE V

                               STOCKHOLDER ACTION
                               ------------------

          Any action required or permitted to be taken by the stockholders of
the Corporation at any annual or special meeting of stockholders of the
Corporation must be effected at a duly called annual or special meeting of
stockholders and may not be taken or effected by a written consent of
stockholders in lieu thereof.


                                   ARTICLE VI

                                   DIRECTORS
                                   ---------

          Section 1.  General.
          ------------------- 

          The business and affairs of the Corporation shall be managed by or
under the direction of the Board of Directors except as otherwise provided
herein or required by law.

          Section 2.  Election of Directors.
          --------------------------------- 

          Election of Directors need not be by written ballot unless the 
By-laws of the Corporation shall so provide.

          Section 3.  Terms of Directors.
          ------------------------------ 

          The number of Directors of the Corporation shall be fixed by
resolution duly adopted from time to time by the Board of Directors.  The
Directors, other than those who may be elected by the holders of any series of
Preferred Stock of the Corporation, shall be classified, with respect to the
term for which they severally hold office, into three classes, as nearly equal
in number as possible.  The initial Class I Directors of the Corporation shall
be Peter J. Smith and Dr. John A. Swanson; the initial Class II Directors of the
Corporation shall be Roger J. Heinen, Jr., Roger B. Kafker and Jacqueline C.
Morby; and the initial Class III Directors of the Corporation shall be Gary B.
Eichhorn and John F. Smith.  The initial Class I Directors shall serve for a
term expiring at the annual meeting of stockholders to be held in 1997, the
initial Class II Directors shall serve for a term expiring at the annual meeting
of stockholders to be held in 1998, and the initial Class III Directors shall
serve for a term expiring at the annual meeting of stockholders to be held in
1999.  At each annual meeting of stockholders, the successor or successors of
the class of Directors whose term expires at that meeting shall be elected by a
plurality of the votes cast at such meeting and shall hold office for a term
expiring at the annual meeting of stockholders held in the third year following
the year of their election.  The Directors

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elected to each class shall hold office until their successors are duly elected
and qualified or until their earlier resignation or removal.


          Notwithstanding the foregoing, whenever, pursuant to the provisions of
Article IV of this Restated Certificate of Incorporation, the holders of any one
or more series of Preferred Stock shall have the right, voting separately as a
series or together with holders of other such series, to elect Directors at an
annual or special meeting of stockholders, the election, term of office, filling
of vacancies and other features of such directorships shall be governed by the
terms of this Restated Certificate of Incorporation and any certificate of
designations applicable thereto, and such Directors so elected shall not be
divided into classes pursuant to this Section 3.

          During any period when the holders of any series of Preferred Stock
have the right to elect additional Directors as provided for or fixed pursuant
to the provisions of Article IV hereof, then upon commencement and for the
duration of the period during which such right continues: (i) the then otherwise
total authorized number of Directors of the Corporation shall automatically be
increased by such specified number of Directors, and the holders of such
Preferred Stock shall be entitled to elect the additional Directors so provided
for or fixed pursuant to said provisions, and (ii) each such additional Director
shall serve until such Director's successor shall have been duly elected and
qualified, or until such Director's right to hold such office terminates
pursuant to said provisions, whichever occurs earlier, subject to such
Director's earlier death, disqualification, resignation or removal.  Except as
otherwise provided by the Board in the resolution or resolutions establishing
such series, whenever the holders of any series of Preferred Stock having such
right to elect additional Directors are divested of such right pursuant to the
provisions of such stock, the terms of office of all such additional Directors
elected by the holders of such stock, or elected to fill any vacancies resulting
from the death, resignation, disqualification or removal of such additional
Directors, shall forthwith terminate and the total and authorized number of
Directors of the Corporation shall be reduced accordingly.

          Section 4. Vacancies.
          -------------------- 

          Subject to the rights, if any, of the holders of any series of
Preferred Stock to elect Directors and to fill vacancies in the Board of
Directors relating thereto, any and all vacancies in the Board of Directors,
however occurring, including, without limitation, by reason of an increase in
size of the Board of Directors, or the death, resignation, disqualification or
removal of a Director, shall be filled solely by the affirmative vote of a
majority of the remaining Directors then in office, even if less than a quorum
of the Board of Directors.  Any Director appointed in accordance with the
preceding sentence shall hold office for the remainder of the full term of the
class of Directors in which the new directorship was created or the vacancy
occurred and until such Director's successor shall have been duly elected and
qualified or until his or her earlier resignation or removal.  Subject to the
rights, if any, of the holders of any series of Preferred Stock to elect 
Directors, when the number of Directors is increased or decreased, the Board 
of Directors shall determine the class or classes to which the increased or 
decreased number of

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Directors shall be apportioned; provided, however, that no decrease in the
number of Directors shall shorten the term of any incumbent Director. In the
event of a vacancy in the Board of Directors, the remaining Directors, except as
otherwise provided by law, may exercise the powers of the full Board of
Directors until the vacancy is filled.

          Section 5. Removal.
          ------------------ 

          Subject to the rights, if any, of any series of Preferred Stock to
elect Directors and to remove any Director whom the holders of any such stock
have the right to elect, any Director (including persons elected by Directors to
fill vacancies in the Board of Directors) may be removed from office (i) only
with cause and (ii) only by the affirmative vote of at least two-thirds of the
total votes which would be eligible to be cast by stockholders in the election
of such Director.  At least 30 days prior to any meeting of stockholders at
which it is proposed that any Director be removed from office, written notice of
such proposed removal shall be sent to the Director whose removal will be
considered at the meeting.  For purposes of this Restated Certificate of
Incorporation, "cause," with respect to the removal of any Director shall mean
only (i) conviction of a felony, (ii) declaration of unsound mind by order of
court, (iii) gross dereliction of duty, (iv) commission of any action involving
moral turpitude, or (v) commission of an action which constitutes intentional
misconduct or a knowing violation of law if such action in either event results
both in an improper substantial personal benefit and a material injury to the
Corporation.


                                  ARTICLE VII

                            LIMITATION OF LIABILITY
                            -----------------------

          A Director of the Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for breach of fiduciary
duty as a Director, except for liability (i) for any breach of the Director's
duty of loyalty to the Corporation or its stockholders, (ii) for acts or
omissions not in good faith or which involve intentional misconduct or a knowing
violation of law, (iii) under Section 174 of the DGCL or (iv) for any
transaction from which the Director derived an improper personal benefit.  If
the DGCL is amended after the effective date of this Restated Certificate of
Incorporation to authorize corporate action further eliminating or limiting the
personal liability of Directors, then the liability of a Director of the
Corporation shall be eliminated or limited to the fullest extent permitted by
the DGCL, as so amended.


          Any repeal or modification of this Article VII by either of (i) the
stockholders of the Corporation or (ii) an amendment to the DGCL, shall not
adversely affect any right or protection existing at the time of such repeal or
modification with respect to any acts or omissions occurring before such repeal
or modification of a person serving as a Director at the time of such repeal or
modification.

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                                  ARTICLE VIII

                              AMENDMENT OF BY-LAWS
                              --------------------

          Section 1. Amendment by Directors
          ---------------------------------

          Except as otherwise provided by law, the By-laws of the Corporation
may be amended or repealed by the Board of Directors.

          Section 2. Amendment by Stockholders
          ------------------------------------

          The By-laws of the Corporation may be amended or repealed at any
annual meeting of stockholders, or special meeting of stockholders called for
such purpose, by the affirmative vote of at least two-thirds of the total votes
eligible to be cast on such amendment or repeal by holders of voting stock,
voting together as a single class; provided, however, that if the Board of
Directors recommends that stockholders approve such amendment or repeal at such
meeting of stockholders, such amendment or repeal shall only require the
affirmative vote of a majority of the total votes eligible to be cast on such
amendment or repeal by holders of voting stock, voting together as a single
class.


                                   ARTICLE IX

                   AMENDMENT OF CERTIFICATE OF INCORPORATION
                   -----------------------------------------

          The Corporation reserves the right to amend or repeal this Restated
Certificate of Incorporation in the manner now or hereafter prescribed by
statute and this Restated Certificate of Incorporation, and all rights conferred
upon stockholders herein are granted subject to this reservation. No amendment
or repeal of this Restated Certificate of Incorporation shall be made unless the
same is first approved by the Board of Directors pursuant to a resolution
adopted by the Board of Directors in accordance with Section 242 of the DGCL,
and, except as otherwise provided by law, thereafter approved by the
stockholders. Whenever any vote of the holders of voting stock is required, and
in addition to any other vote of holders of voting stock that is required by
this Restated Certificate of Incorporation or by law, the affirmative vote of a
majority of the total votes eligible to be cast by holders of voting stock with
respect to such amendment or repeal, voting together as a single class, at a
duly constituted meeting of stockholders called expressly for such purpose shall
be required to amend or repeal any provisions of this Restated Certificate of
Incorporation; provided, however, that the affirmative vote of not less than 80%
of the total votes eligible to be cast by holders of voting stock, voting
together as a single class, shall be required to amend or repeal any of the
provisions of Article VI or Article IX of this Restated Certificate of
Incorporation .

                                       8

 
          I, Peter J. Smith, President of the Corporation, for the purpose of
restating the Corporation's Third Amended and Restated Certificate of
Incorporation pursuant to the General Corporation Law of the State of Delaware,
do make this certificate, hereby declaring and certifying that this is my act
and deed on behalf of the Corporation this 10th day of July, 1996.



                         /s/ Peter J. Smith
                         --------------------------------                       
                         Peter J. Smith, President

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