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                                                                   EXHIBIT 10.17


                              SEVERANCE AGREEMENT


  THIS SEVERANCE AGREEMENT ("Agreement") is made and entered into as of the 15th
day of November, 1999, by and between Sterling Software, Inc., a Delaware
corporation ("Sterling Software"), and Geno P. Tolari, an individual
("Executive").

                                   RECITALS:

     WHEREAS, Sterling Software acquires, develops, markets and supports a broad
range of products and services; and

     WHEREAS, Sterling Software desires to continue to retain Executive as its
Executive Vice President and Chief Operating Officer; and

     WHEREAS, Executive is willing to continue to accept and fulfill such
responsibilities;

     NOW, THEREFORE, in consideration of the premises and covenants contained
herein and other good and valuable consideration, the sufficiency of which is
hereby acknowledged, the parties hereto agree as follows:

                                  AGREEMENTS:

     1.   Employment.  Executive agrees to render such managerial services as
          ----------
          are customarily required of the Executive Vice President and Chief
          Operating Officer.

     2.   Term.  This Agreement shall commence on the date first set forth above
          ----
          and shall continue in effect for sixty (60) months after the "Notice
          Date" as defined in Section 3 hereof.

     3.   Termination of Employment.  The parties acknowledge that Executive is
          -------------------------
          employed "at will" and may be terminated by Sterling Software at any
          time with or without cause.  Executive shall be entitled to
          termination pay calculated in accordance with Section 4 hereof upon
          receiving notice of the intended termination of Executive's employment
          by Sterling Software, with or without cause.

          The date on which a notice of termination is given to Executive by
          Sterling Software (whether orally or in writing) shall be deemed the
          "Notice Date" with the termination to be effective sixty (60) months
          following the Notice Date. On the Notice Date, Executive shall be
          deemed to have been assigned "no duties," shall vacate his or her
          office and shall resign as an officer of Sterling Software and its
          subsidiaries. Since Executive will be assigned "no duties" with
          Sterling Software,
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          Executive shall be free to pursue other employment or consulting
          opportunities during the 60-month period in which Executive receives
          termination pay.

     4.   Termination Pay.  For purposes of this Agreement, if Executive's
          ---------------
          employment is terminated pursuant to Section 3, upon receipt from
          Executive (or Executive's estate or personal representative) of a
          fully executed release in form reasonably acceptable to Sterling
          Software, Sterling Software shall pay, or cause one of its
          subsidiaries to pay, to Executive as termination pay:

          (a)  an amount equal to 500 hundred percent of Executive's annual base
               salary rate in effect immediately prior to the Notice Date; and

          (b)  an amount equivalent to the product of five times:

               (i)   100% of the Plan Bonus Amount (as hereinafter defined) in
                     effect immediately prior to the Notice Date, or

               (ii)  if no Plan Bonus Amount shall be in effect or readily
                     determinable by Sterling Software with respect to Executive
                     immediately prior to the Notice Date, an amount equal to
                     the aggregate amount of the bonus, incentive or other cash
                     compensation, in addition to (but not including)
                     Executive's annual base salary, received by Executive
                     pursuant to any bonus, incentive compensation, performance,
                     discretionary pay or similar agreement, policy, plan,
                     program or arrangement (whether or not funded) of Sterling
                     Software during the 365 days immediately prior to the
                     Notice Date.

               As used herein, the term "Plan Bonus Amount" shall mean the
               aggregate amount (calculated to avoid duplication, on an
               annualized basis and with respect only to the fiscal year of
               Sterling Software in which the Notice Date occurs) of the
               budgeted or otherwise authorized or contemplated bonus, incentive
               or other cash compensation, in addition to (but not including)
               Executive's base salary, to be paid to Executive under any bonus,
               incentive compensation, performance, discretionary pay or similar
               agreement, policy, plan, program or arrangement (whether or not
               funded) of Sterling Software upon the attainment of 100% of the
               objective(s) and 100% of the planned or targeted amount(s)
               specified in or pursuant to such agreement, policy, plan, program
               or arrangement, whether or not attained as of the Notice Date.

          In the event of Executive's death or disability following the Notice
          Date, Executive, Executive's estate or Executive's personal
          representative, as the case may be, shall continue to receive the
          termination payments provided for in this Section 4.

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     5.   Disbursement of Termination Pay.  The aggregate amount of all
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          termination payments that are payable to Executive as provided in
          Section 4 hereof shall be determined in good faith by Sterling
          Software within 15 days following the Notice Date, and such
          termination payments shall be distributed by Sterling Software to
          Executive in one hundred twenty (120) equal twice monthly installments
          beginning thirty (30) days following the Notice Date and continuing
          twice monthly thereafter.

     6.   Continuation of Insurance Benefits.  For a period of sixty (60) months
          ----------------------------------
          following the Notice Date, Sterling Software shall arrange to provide
          Executive, at no additional charge to Executive, with life, medical,
          dental, vision, health, accident and disability insurance benefits
          substantially similar to those that Executive is receiving or is
          entitled to receive immediately prior to the Notice Date, which
          benefits shall in no event be less than those benefits in effect
          immediately prior to the Notice Date.

     7.   Continued Participation in Employee Plans.  For a period of sixty (60)
          -----------------------------------------
          months following the Notice Date, Executive shall, to the fullest
          extent permitted by applicable law, be permitted to continue to
          participate in Sterling Software's Deferred Compensation Plan, Savings
          and Security (401(k)) Plan and any other similar plan that may be
          adopted prior to the Notice Date for the benefit and retention of
          Sterling Software's executive officers.  In no event will Sterling
          Software be required after the Notice Date to make any new grants of
          stock options to such Executive under any Sterling Software stock
          option plan or otherwise.

     8.   Change-in-Control.  Sterling Software and Executive are parties to a
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          Change-in-Control Severance Agreement, dated as of November 15, 1999
          (as such agreement may be amended from time to time, the "Change-in-
          Control Agreement").  Notwithstanding anything contained in this
          Agreement to the contrary, in the event the Notice Date occurs under
          circumstances in which Executive would otherwise be entitled to
          receive payments and benefits under both this Agreement and the
          Change-in-Control Agreement, Executive shall have the right to elect
          to receive payments and benefits under either this Agreement or the
          Change-in-Control Agreement, but not both.  Within five business days
          following the Notice Date under circumstances in which this Section 8
          would apply, Sterling Software shall provide Executive, in writing, a
          reasonably detailed determination of the payments and other benefits
          under each of this Agreement and the Change-in-Control Agreement.
          Executive shall make the election provided for in this Section 8
          within thirty calendar days after Executive's receipt of the written
          determination referred to in the preceding sentence; provided,
          however, that if such election is not so made within such 30-day
          period, Executive shall be irrevocably deemed to have elected to
          receive payments and benefits under the

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          Change-in-Control Agreement. Prior to the date on which Executive
          makes or is deemed to have made the election referred to above, he
          shall receive all benefits under Sections 4, 5, 6 and 7 of this
          Agreement as if Executive had made the election to receive benefits
          and payments under this Agreement.

      9.  Miscellaneous.
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          (i)    Notices, demands, payments, reports and correspondence shall be
                 addressed to the parties hereto at the address for such party
                 set forth below or such other places as may from time to time
                 be designated in writing to the other party. Notices hereunder
                 shall be deemed to be given on the date such notices are
                 actually received.

                 If to Sterling Software, to:  Sterling Software, Inc.
                                               300 Crescent Court, Suite 1200
                                               Dallas, Texas 75201
                                               Attention: President

                 If to Executive, to:          Geno P. Tolari
                                               c/o Sterling Software, Inc.
                                               300 Crescent Court, Suite 1200
                                               Dallas, Texas 75201

          (ii)   This Agreement shall be binding upon Sterling Software and
                 Executive and their respective successors, assigns, heirs and
                 personal representatives.

          (iii)  The substantive laws of the State of Delaware shall govern the
                 validity, construction, enforcement and interpretation of the
                 provisions of this Agreement.

          (iv)   No provision of this Agreement may be modified, waived or
                 discharged unless such waiver, modification or discharge is
                 agreed to in writing signed by Executive and Sterling Software.
                 No waiver by either party hereto at any time of any breach by
                 the other party hereto or compliance with any condition or
                 provision of this Agreement to be performed by such other party
                 will be deemed a waiver of similar or dissimilar provisions or
                 conditions at the same or at any prior or subsequent time. No
                 agreements or representations, oral or otherwise, expressed or
                 implied with respect to the subject matter hereof have been
                 made by either party which are not set forth expressly in this
                 Agreement. References to Sections are to references to Sections
                 of this Agreement.

      10. Termination of Prior Agreements.  Upon the execution and delivery of
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          this Agreement, the Severance Agreement between Executive and Sterling
          Software,

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          dated February 12, 1996, as amended to the date hereof (the "Prior
          Agreement"), shall terminate automatically and shall thereafter be of
          no further force or effect; provided, however, that if this Agreement
          is held by a court of competent jurisdiction to be wholly invalid,
          unenforceable or otherwise illegal, the preceding clause shall have no
          effect and the Prior Agreement shall be deemed to have continued at
          all times in force and effect. Subject to the foregoing proviso, this
          Agreement supersedes all prior agreements, arrangements and
          understandings with respect to the subject matter hereof, excluding,
          however, the Change-in-Control Agreement.

    Executed by the parties hereto as of the date first set forth above.


                                          EXECUTIVE



                                          ------------------------------------
                                          Geno P. Tolari


                                          STERLING SOFTWARE, INC.



                                          By:
                                             ---------------------------------
                                             Sterling L. Williams,
                                             President and
                                             Chief Executive Officer

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