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                                                                     Exhibit 3.1
                                                                     -----------


                     RESTATED CERTIFICATE OF INCORPORATION
                                      OF
                            STERLING SOFTWARE, INC.

     Sterling Software, Inc., a Delaware corporation (the "corporation"), does
hereby certify that this Restated Certificate of Incorporation was duly adopted
in accordance with Section 245 of the General Corporation Law of the State of
Delaware; and the corporation's original Certificate of Incorporation was filed
with the Delaware Secretary of State on February 14, 1983.  This Restated
Certificate of Incorporation restates and integrates, but does not further amend
the provisions of the Certificate of Incorporation of this corporation as
heretofore amended or supplemented, and there is no discrepancy between those
provisions and the provisions of this Restated Certificate of Incorporation
which is hereby restated to read in its entirety as follows:

     FIRST.  The name of the corporation is Sterling Software, Inc.
     -----

     SECOND.  The address of the corporation's registered office in the State of
     ------
Delaware is 1013 Centre Road, City of Wilmington, County of New Castle, Delaware
19805.  The name of the Corporation's registered agent at such address is The
Corporation Service Company.

     THIRD. 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 General Corporation Law of Delaware.

     FOURTH.  Section 1.  Authorized Capital Stock.  The total number of shares
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of stock of all classes which the corporation shall have authority to issue is
Two Hundred Sixty Million (260,000,000), consisting of Two Hundred Fifty Million
(250,000,000) shares of Common Stock having a par value of $.10 per share, and
Ten Million (10,000,000) shares of Preferred Stock having a par value of $.10
per share.

     Section 2.  Common Stock.  Shares of Common Stock and, subject to the
                 ------------
provisions of this Article Fourth, shares of any series of Preferred Stock may
be issued from time to time as the corporation's board of directors (the "Board
of Directors") determines and on such terms and for such consideration as may be
fixed by the Board of Directors.

     Subject to the provisions of law and the preferences of the Preferred
Stock, dividends may be paid on the Common Stock at such time and in such
amounts as the Board of Directors may deem advisable.

     The authorized amount of shares of Common Stock and of Preferred Stock may,
without a class or series vote, be increased or decreased from time to time by
the affirmative vote of the holders of a majority of the stock of the
corporation entitled to a vote thereon.

     Except as otherwise specifically required by law or as specifically
provided in any resolution or resolutions of the Board of Directors providing
for the issue of any particular

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series of Preferred Stock, the exclusive voting power of the corporation shall
be vested in the Common Stock of the corporation. Each share of Common Stock
shall entitle the holder thereof to one vote at all meetings of the stockholders
of the corporation.

  Section 3.  Preferred Stock.  The Preferred Stock may be issued in one or more
              ---------------
series as may be determined from time to time by the Board of Directors.  The
Preferred Stock of each such series shall have such voting powers, full or
limited, or no voting powers, and such designations, preferences, and relative,
participating, optional, redemption, conversion, exchange or other special
rights, and qualifications, limitations or restrictions thereof, as shall be
stated and expressed by the Board of Directors in the resolution or resolutions
providing for the issue of such series of Preferred Stock pursuant to the
authority to do so which is hereby expressly vested in the Board of Directors.

  Except as otherwise provided in any resolution or resolutions of the Board of
Directors providing for the issue of any particular series of Preferred Stock,
the number of shares of stock of any such series so set forth in such resolution
or resolutions may be increased or decreased (but not below the number of shares
of such series then outstanding) by a resolution or resolutions likewise adopted
by the Board of Directors.  No approval by class or series vote or otherwise, of
the holders of the Preferred Stock or any series thereof will be required for
the issue by the Board of Directors of any other series of Preferred Stock,
whether or not in any respect senior to or on a parity with any such outstanding
series, provided, however, that the Board of Directors may condition the issue
of such additional series of Preferred Stock on the approval, by such proportion
as the Board of Directors may specify, of any such outstanding series.

  Except as otherwise provided in any resolution or resolutions of the Board of
Directors providing for the issue of any particular series of Preferred Stock,
Preferred Stock redeemed or otherwise acquired by the corporation shall assume
the status of authorized but unissued Preferred Stock and shall be unclassified
as to series and may thereafter, subject to the provisions of this Article
Fourth and to any restrictions contained in any resolution or resolutions of the
Board of Directors providing for the issue of any such series of Preferred
Stock, be reissued in the same manner as other authorized but unissued Preferred
Stock.

  Section 3.1  Series A Junior Participating Preferred Stock.  Pursuant to
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authority vested in the Board of Directors by its Certificate of Incorporation,
as theretofore amended, and pursuant to the provisions of Section 151 of the
Delaware General Corporation Law, the corporation's board of directors on
December 26, 1996 created a series of Preferred Stock designated Series A Junior
Participating Preferred Stock and a Certificate of Designations of the Series A
Junior Participating Preferred Stock was filed with the Delaware Secretary of
State.  Pursuant to authority vested in the Board of Directors by its
Certificate of Incorporation, as theretofore amended, and the Delaware General
Corporation Law, the Board of Directors on March 11, 1998 adopted a resolution
providing for the amendment and restatement of the Certificate of Designations
of the Series A Junior Participating Preferred Stock solely to effect an
increase in the number of shares constituting such Series A Junior Participating
Preferred Stock and an Amended Certificate of Designations of Series A Junior
Participating Preferred Stock (the

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"Amended Certificate of Designations") was filed with the Delaware Secretary of
State on March 11, 1998. The designation and amount thereof and the voting
powers, preferences and relative, participating, optional and other special
rights of the shares of Series A Junior Participating Preferred Stock, and the
qualifications, limitations or restrictions thereof, shall continue in all
respects as set forth in the Amended Certificate of Designations, but for
convenience of reference only are set forth in full below:

     (a)  Designation and Amount. The shares of such series will be designated
     as Series A Junior Participating Preferred Stock (the "Series A Preferred")
     and the number of shares constituting the Series A Preferred is 1,250,000.
     Such number of shares may be increased or decreased by resolution of the
     Board of Directors; provided, however, that no decrease will reduce the
                         --------  -------
     number of shares of Series A Preferred to a number less than the number of
     shares then outstanding plus the number of shares reserved for issuance
     upon the exercise of outstanding options, rights or warrants or upon the
     conversion of any outstanding securities issued by the corporation
     convertible into shares of Series A Preferred.

     (b)  Dividends and Distribution.

          (1) Subject to the rights of the holders of any shares of any series
     of Preferred Stock ranking prior to the shares of Series A Preferred with
     respect to dividends, the holders of shares of Series A Preferred, in
     preference to the holders of Common Stock of the corporation, and of any
     other junior stock, will be entitled to receive, when, as and if declared
     by the Board of Directors out of funds legally available for the purpose,
     dividends payable in cash on such dates as are from time to time
     established for the payment of cash dividends on the Common Stock (each
     such date being referred to herein as a "Dividend Payment Date"),
     commencing on the first Dividend Payment Date after the first issuance of a
     share or fraction of a share of Series A Preferred (the "First Dividend
     Payment Date"), in an amount per share (rounded to the nearest cent) equal
     to the greater of (i) $1.00 or (ii) subject to the provision for adjustment
     hereinafter set forth, one hundred times the aggregate per share amount of
     all cash dividends, and one hundred times the aggregate per share amount
     (payable in kind) of all non-cash dividends or other distributions, other
     than a dividend payable in shares of Common Stock or a subdivision of the
     outstanding shares of Common Stock (by reclassification or otherwise),
     declared on the Common Stock since the immediately preceding Dividend
     Payment Date or, with respect to the First Dividend Payment Date, since the
     first issuance of any share or fraction of a share of Series A Preferred.
     In the event that the corporation at any time after the filing of the
     Amended Certificate of Designations with the Delaware Secretary of State
     (i) declares a dividend on the outstanding shares of Common Stock payable
     in shares of Common Stock, (ii) subdivides the outstanding shares of Common
     Stock, (iii) combines the outstanding shares of Common Stock into a smaller
     number of shares, or (iv) issues any shares of its capital stock in a
     reclassification of the outstanding shares of Common Stock (including any
     such reclassification in connection with a consolidation or merger in which
     the corporation is the continuing or surviving corporation), then, in each
     such case and regardless of

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     whether any shares of Series A Preferred are then issued or outstanding,
     the amount to which holders of shares of Series A Preferred would otherwise
     be entitled immediately prior to such event under clause (ii) of the
     preceding sentence will be adjusted by multiplying such amount by a
     fraction, the numerator of which is the number of shares of Common Stock
     outstanding immediately after such event and the denominator of which is
     the number of shares of Common Stock that were outstanding immediately
     prior to such event.

          (2)  Dividends will accrue on outstanding shares of Series A Preferred
     from the Dividend Payment Date next preceding the date of issue of such
     shares, unless (i) the date of issue of such shares is prior to the record
     date for the First Dividend Payment Date, in which case dividends on such
     shares will accrue from the date of the first issuance of a share of Series
     A Preferred or (ii) the date of issue is a Dividend Payment Date or is a
     date after the record date for the determination of holders of shares of
     Series A Preferred entitled to receive a dividend and before such Dividend
     Payment Date, in either of which events such dividends will accrue from
     such Dividend Payment Date. Accrued but unpaid dividends will cumulate from
     the applicable Dividend Payment Date but will not bear interest. Dividends
     paid on the shares of Series A Preferred in an amount less than the total
     amount of such dividends at the time accrued and payable on such shares
     will be allocated pro rata on a share-by-share basis among all such shares
     at the time outstanding. The Board of Directors may fix a record date for
     the determination of holders of shares of Series A Preferred entitled to
     receive payment of a dividend or distribution declared thereon, which
     record date will be not more than 60 calendar days prior to the date fixed
     for the payment thereof.

     (c)  Voting Rights.  The holders of shares of Series A Preferred will have
     the following voting rights:

          (1)  Subject to the provision for adjustment hereinafter set forth,
     each share of Series A Preferred will entitle the holder thereof to one
     hundred votes on all matters submitted to a vote of the stockholders of the
     corporation. In the event the corporation at any time after the filing of
     the Amended Certificate of Designations with the Delaware Secretary of
     State (i) declares a dividend on the outstanding shares of Common Stock
     payable in shares of Common Stock, (ii) subdivides the outstanding shares
     of Common Stock, (iii) combines the outstanding shares of Common Stock into
     a smaller number of shares, or (iv) issues any shares of its capital stock
     in a reclassification of the outstanding shares of Common Stock (including
     any such reclassification in connection with a consolidation or merger in
     which the corporation is the continuing or surviving corporation), then, in
     each such case and regardless of whether any shares of Series A Preferred
     are then issued or outstanding, the number of votes per share to which
     holders of shares of Series A Preferred would otherwise be entitled
     immediately prior to such event will be adjusted by multiplying such number
     by a fraction, the numerator of which is the number of shares of Common
     Stock outstanding immediately after such event and the denominator of which
     is

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<PAGE>

     the number of shares of Common Stock that were outstanding immediately
     prior to such event.

          (2)  Except as otherwise provided herein, in any other Preferred Stock
     Designation creating a series of Preferred Stock or any similar stock, or
     by law, the holders of shares of Series A Preferred and the holders of
     shares of Common Stock and any other capital stock of the corporation
     having general voting rights will vote together as one class on all matters
     submitted to a vote of stockholders of the corporation.

          (3)  Except as set forth herein, or as otherwise provided by law,
     holders of shares of Series A Preferred will have no voting rights.

     (d)  Certain Restrictions.

          (1)  Whenever dividends or other distributions payable on the Series A
     Preferred are in arrears, thereafter and until all accrued and unpaid
     dividends and distributions, whether or not declared, on shares of Series A
     Preferred outstanding have been paid in full, the corporation will not:

               (i)    Declare or pay dividends, or make any other distributions,
          on any shares of stock ranking junior (either as to dividends or upon
          liquidation, dissolution or winding up) to the shares of Series A
          Preferred;

               (ii)   Declare or pay dividends, or make any other distributions,
          on any shares of stock ranking on a parity (either as to dividends or
          upon liquidation, dissolution, or winding up) with the shares of
          Series A Preferred, except dividends paid ratably on the shares of
          Series A Preferred and all such parity stock on which dividends are
          payable or in arrears in proportion to the total amounts to which the
          holders of all such shares are then entitled;

               (iii)  Redeem, purchase or otherwise acquire for consideration
          shares of any stock ranking junior (either as to dividends or upon
          liquidation, dissolution or winding up) to the shares of Series A
          Preferred; provided, however, that the corporation may at any time
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          redeem, purchase or otherwise acquire shares of any such junior stock
          solely in exchange for shares of any stock of the corporation ranking
          junior (either as to dividends or upon dissolution, liquidation or
          winding up) to the shares of Series A Preferred; or

               (iv)   Redeem, purchase or otherwise acquire for consideration
          any shares of Series A Preferred, or any shares of stock ranking on a
          parity with the shares of Series A Preferred, except in accordance
          with a purchase offer made in writing or by publication (as determined
          by the Board of Directors) to all holders of such shares upon such
          terms as the

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<PAGE>

          Board of Directors, after consideration of the respective annual
          dividend rates and other relative rights and preferences of the
          respective series and classes, may determine in good faith will result
          in fair and equitable treatment among the respective series or
          classes.

          (2)  The corporation will not permit any majority-owned subsidiary
     of the corporation to purchase or otherwise acquire for consideration any
     shares of stock of the corporation unless the corporation could, under
     paragraph (1) of this subsection (d), purchase or otherwise acquire such
     shares at such time and in such manner.

     (e)  Reacquired Shares.  Any shares of Series A Preferred purchased or
     otherwise acquired by the corporation in any manner whatsoever will be
     retired and canceled promptly after the acquisition thereof.  All such
     shares will upon their cancellation become authorized but unissued shares
     of Preferred Stock and may be reissued as part of a new series of Preferred
     Stock subject to the conditions and restrictions on issuance set forth
     herein, or in any other Preferred Stock Designation creating a series of
     Preferred Stock or any similar stock or as otherwise required by law.

     (f)  Liquidation, Dissolution or Winding Up.  Upon any liquidation,
     dissolution or winding up of the corporation, no distribution will be made
     (1) to the holders of shares of stock ranking junior (either as to
     dividends or upon liquidation, dissolution, or winding up) to the shares of
     Series A Preferred unless, prior thereto, the holders of shares of Series A
     Preferred have received $100 per share, plus an amount equal to accrued and
     unpaid dividends and distributions thereon, whether or not declared, to the
     date of such payment; provided, however, that the holders of shares of
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     Series A Preferred will be entitled to receive an aggregate amount per
     share, subject to the provision for adjustment hereinafter set forth, equal
     to one hundred times the aggregate amount to be distributed per share to
     holders of shares of Common Stock or (2) to the holders of shares of stock
     ranking on a parity (either as to dividends or upon liquidation,
     dissolution, or winding up) with the shares of Series A Preferred, except
     distributions made ratably on the shares of Series A Preferred and all such
     parity stock in proportion to the total amounts to which the holders of all
     such shares are entitled upon such liquidation, dissolution, or winding up.
     In the event the corporation at any time after the filing of the Amended
     Certificate of Designations with the Delaware Secretary of State (i)
     declares a dividend on the outstanding shares of Common Stock payable in
     shares of Common Stock, (ii) subdivides the outstanding shares of Common
     Stock, (iii) combines the outstanding shares of Common Stock into a smaller
     number of shares, or (iv) issues any shares of its capital stock in a
     reclassification of the outstanding shares of Common Stock (including any
     such reclassification in connection with a consolidation or merger in which
     the corporation is the continuing or surviving corporation), then, in each
     such case and regardless of whether any shares of Series A Preferred are
     then issued or outstanding, the aggregate amount to which each holder of
     shares of Series A

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<PAGE>

     Preferred would otherwise be entitled immediately prior to such event under
     the proviso in clause (1) of the preceding sentence will be adjusted by
     multiplying such amount by a fraction, the numerator of which is the number
     of shares of Common Stock outstanding immediately after such event and the
     denominator of which is the number of shares of Common Stock that were
     outstanding immediately prior to such event.

     (g)  Consolidation, Merger, Etc. In the event that the corporation enters
     into any consolidation, merger, combination or other transaction in which
     the shares of Common Stock are exchanged for or changed into other stock or
     securities, cash and/or any other property, then, in each such case, each
     share of Series A Preferred will at the same time be similarly exchanged
     for or changed into an amount per share, subject to the provision for
     adjustment hereinafter set forth, equal to one hundred times the aggregate
     amount of stock, securities, cash and/or any other property (payable in
     kind), as the case may be, into which or for which each share of Common
     Stock is changed or exchanged. In the event the corporation at any time
     after the filing of the Amended Certificate of Designations with the
     Delaware Secretary of State (1) declares a dividend on the outstanding
     shares of Common Stock payable in shares of Common Stock, (2) subdivides
     the outstanding shares of Common Stock, (3) combines the outstanding shares
     of Common Stock in a smaller number of shares, or (4) issues any shares of
     its capital stock in a reclassification of the outstanding shares of Common
     Stock (including any such reclassification in connection with a
     consolidation or merger in which the corporation is the continuing or
     surviving corporation), then, in each such case and regardless of whether
     any shares of Series A Preferred are then issued or outstanding, the amount
     set forth in the preceding sentence with respect to the exchange or change
     of shares of Series A Preferred will be adjusted by multiplying such amount
     by a fraction, the numerator of which is the number of shares of Common
     Stock outstanding immediately after such event and the denominator of which
     is the number of shares of Common Stock that were outstanding immediately
     prior to such event.

     (h)  Redemption.  The shares of Series A Preferred are not redeemable.

     (i)  Rank.  The shares of Series A Preferred rank, with respect to the
     payment of dividends and the distribution of assets, junior to all other
     series of the corporation's Preferred Stock.

     (j)  Amendment.  Notwithstanding anything contained herein to the contrary
     and in addition to any other vote required by applicable law, the
     Certificate of Incorporation of the corporation may not be amended in any
     manner that would materially alter or change the powers, preferences or
     special rights of the Series A Preferred so as to affect them adversely
     without the affirmative vote of the holders of at least 80% of the
     outstanding shares of Series A Preferred, voting together as a single
     series.

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<PAGE>

  FIFTH.  In furtherance and not in limitation of the powers conferred by the
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laws of the State of Delaware, the Board of Directors is expressly authorized to
make, alter or repeal the Bylaws of the corporation.

  SIXTH.  All power of the corporation shall be exercised by or under the
  -----
direction of the Board of Directors except as otherwise provided herein or
required by law.

  For the management of the business and for the conduct of the affairs of the
corporation, and in further creation, definition, limitation and regulation of
the power of the corporation and of its directors and of its stockholders, it is
further provided:

     Section 1.  Election  of  Directors.  Election of directors need not be by
                 -----------------------
  written ballot unless the Bylaws of the corporation shall so provide.

     Section 2.  Number, Election and  Term of Directors.  Except as otherwise
                 ---------------------------------------
  fixed pursuant to the provisions of Article Fourth hereof relating to the
  rights of the holders of any class or series of stock having a preference over
  the Common Stock as to dividends or upon liquidation to elect additional
  directors under specified circumstances, the number of directors of the
  corporation shall be fixed from time to time by or pursuant to the Bylaws. The
  directors, other than those who may be elected by the holders of any class or
  series of stock having preference over the Common Stock as to dividends or
  upon liquidation, shall be classified, with respect to the time for which they
  severally hold office, into three classes, as nearly equal in number as
  possible, as shall be provided in the manner specified in the Bylaws, one
  class to hold office initially for a term expiring at the annual meeting of
  stockholders to be held in 1988, another class to hold office initially for a
  term expiring at the annual meeting of stockholders to be held in 1989, and
  another class to hold office initially for a term expiring at the annual
  meeting of stockholders to be held in 1990, with members of each class to hold
  office until their successors are elected and qualified. At each annual
  meeting of the stockholders of the corporation, the successors to the class of
  directors whose term expires at that meeting shall be elected to hold office
  for a term expiring at the annual meeting of stockholders held in the third
  year following the year of their election.

     Section 3.  Stockholder Nomination of a Director.  Advance notice of
                 ------------------------------------
  nominations for the election of directors, other than by the Board of
  Directors or a Committee thereof, shall be given in the manner provided by the
  Bylaws.

     Section 4.  Amendment, Repeal, etc.  Notwithstanding anything contained
                 ----------------------
  in this Restated Certificate of Incorporation to the contrary, the affirmative
  vote of the holders of at least 75% of the voting power of all shares of the
  corporation entitled to vote generally in the election of directors, voting
  together as a single class, shall be required to alter, amend or adopt any
  provision inconsistent with, or repeal, this Article Sixth or any provision
  hereof.

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     SEVENTH:  The corporation reserves the right to amend, alter, change or
     -------
repeal any provision contained in this Restated Certificate of Incorporation, to
the extent and in the manner now or hereafter prescribed by the laws of the
State of Delaware, and additional provisions authorized by such laws as are then
in force may be added hereto. All rights conferred upon the directors, officers
and stockholders of the corporation herein or in any amendment hereof are
granted subject to this reservation.

     EIGHTH:  To the fullest extent permitted by the Delaware General
     ------
Corporation Law as the same exists or may hereafter be amended, a director of
the corporation shall not be liable to the corporation or its stockholders for
monetary damages for breach of fiduciary duty as a director.

     NINTH:   No action required to be taken, or which may be taken, at any
     -----
annual or special meeting of stockholders of the corporation may be taken
without a meeting, and the power of stockholders to consent in writing, without
a meeting, to the taking of any action is specifically denied.

     IN WITNESS WHEREOF, we have signed this Restated Certificate of
Incorporation this 4th day of November, 1999.


                                             STERLING SOFTWARE, INC.



                                             By:  /s/ Don J. McDermett, Jr.
                                                  --------------------------
                                                  Don J. McDermett, Jr.
                                                  Senior Vice President,
                                                  General Counsel and Secretary

ATTEST:



/s/ Mark H. Kleinman
--------------------------
Mark H. Kleinman
Assistant Secretary and
Assistant General Counsel

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