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                                                                    EXHIBIT 10.1

                            STERLING SOFTWARE, INC.

                   SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN II
                   -----------------------------------------

                                   PREAMBLE
                                   --------

The purpose of this Supplemental Executive Retirement Plan (this "Plan") is to
continue the benefits accrued by Geno P. Tolari under the Informatics General
Corporation Supplemental Executive Retirement Plan II (the "Previous Plan").
This Plan amends and supersedes, effective as of January 1, 1990, the Previous
Plan in its entirety with respect to the Previous Plan benefits of Geno P.
Tolari.

                                   SECTION I
                                   ---------
                                  Definitions
                                  -----------

1.1   "Basic Plan Benefit" has the meaning set forth in Section 3.1.

1.2   "Code" means the Internal Revenue Code of 1986, as may be amended from
      time to time.

1.3   "Committee" means the Executive Committee of the Board of Directors of the
      Company (excluding, however, the Participant), which has been given
      authority by the Board of Directors to administer this Plan.

1.4   "Company" means Sterling Software, Inc.

1.5   "CPI" means the Consumer Price Index or appropriate equivalent index as
      determined by the Committee.

1.6   "Earnings" means base salary payable plus cash incentive compensation
      payable for a calendar year, but excluding all incentive cash compensation
      in excess of 50% of base salary in the calendar year in which such
      incentive awards are received by the Participant or, if the Participant
      elects to defer receipt of all or part of such incentive awards pursuant
      to the Company's Deferred Compensation Plan or otherwise, in the calendar
      year in which such incentive awards first would have been received by the
      Participant, averaged over the highest consecutive three years of Service.
      Notwithstanding any provision contained herein, the limitation for
      recognition of incentive cash compensation as "Earnings" contained in the
      previous sentence shall be applied to the Participant's base salary for
      his last full calendar year of Service in determining such limitation with
      respect to the Participant's incentive compensation for his last full
      calendar year of Service. Salary deferred by the election of the
      Participant pursuant to the Company's Deferred Compensation Plan or
      otherwise shall be included in Earnings in the calendar year for which
      such salary relates (i.e., the year in which the related services are
      performed), cash incentive compensation so deferred shall be included in
      Earnings in the calendar year in which, but for such deferral, such
      incentive compensation first would have been received, and deferred
      compensation (both salary and incentive compensation) that is included in
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      Earnings pursuant to this sentence shall not be included in Earnings when
      it is later actually received by the Participant. For example, annual
      incentive cash compensation is earned in calendar year 1995 in the amount
      of $80,000 and is paid in calendar year 1996. The $80,000 paid in 1996 is
      compared to a $120,000 1996 base salary. Since $80,000 is greater than
      $60,000 (50% of 1996 base salary) only $60,000 of the award will be used
      towards Earnings for 1995 under the Plan. The Earnings for 1995 would be
      the same even if the Participant deferred receipt of all or a portion of
      the $80,000 or $120,000 until some time after 1996. "Monthly Earnings"
      means Earnings divided by twelve.

1.7   "Informatics Plan" means the Informatics General Corporation Retirement
      Plan, a terminated money purchase pension plan.

1.8   "Participant" means Geno P. Tolari.

1.9   "Plan" means the Sterling Software, Inc. Supplemental Executive Retirement
      Plan II.

1.10  "Retirement" means the termination of the Participant's employment with
      the Company on one of the retirement dates specified in Section 2.1.

1.11  "Service" means the Participant's months of service from October 5, 1970,
      his date of hire by Informatics General Corporation, to Retirement. Such
      service will include without duplication periods of employment with
      Informatics General Corporation; the Company; and any of their
      subsidiaries, affiliates, or successors. If the Participant becomes
      disabled and is receiving long-term disability benefits from the Company's
      Long-Term Disability Plan, such period shall be considered Service under
      this Plan.

1.12  "Severance Agreement" means either or both of the Severance Agreement
      dated November 15, 1999 and/or the Change in Control Severance Agreement
      dated November 15, 1999, both between the Company and the Participant, as
      well as any amendments made to such agreements.

1.13  "Surviving Spouse" means the Participant's spouse married to him for at
      least one year prior to the earlier of the Participant's death or
      Retirement.

1.14  The singular may include the plural, unless the context clearly indicates
      the contrary.

                                  SECTION II
                                  ----------
                           Eligibility for Benefits
                           ------------------------

2.1   Subject to Section IV of this Plan, the Participant is eligible to retire
      and receive a benefit under this Plan beginning on one of the following
      dates.

      (a)  "Normal Retirement Date," which is the first day of the month
           following the month in which the Participant reaches age 65.

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      (b)  "Early Retirement Date," which is the first day of any month before
           the Normal Retirement Date or Disability Retirement Date, following
           the month in which the Participant reaches age 55 and has 15 or more
           years of Service.

      (c)  "Postponed Retirement Date," with the Committee's consent, which is
           the first day of the month following the Participant's Normal
           Retirement Date in which the Participant terminates employment with
           the Company.

      (d)  "Disability Retirement Date," which is the first day of the month in
           which the Participant begins receiving a long-term disability benefit
           from the Company's Long-Term Disability Plan.

                                  SECTION III
                                  -----------
                               Amount of Benefit
                               -----------------

3.1   The monthly retirement benefit payable to the Participant if he retires at
      his Normal Retirement Date or his Postponed Retirement Date under the Plan
      will equal the lessor of (i) or (ii), where

      (i)    is equal to 1/6 of 1% times months of Service times Monthly
             Earnings; and

      (ii)   is equal to 50% of Monthly Earnings less the Basic Plan Benefit (as
             hereinafter defined).

     For purposes of the Plan, the term "Basic Plan Benefit" means the monthly
     annuity payment (as hereinafter determined), payable (x) in the form of a
     50% joint and survivor annuity to the Participant if he has a Surviving
     Spouse at the Normal Retirement Date or Postponed Retirement Date; or (y)
     if the Participant does not have a Surviving Spouse at such time, in the
     form of a single life annuity, that could be provided by the accumulation
     with interest of 3% of Compensation for each calendar year of the
     Participant's Service beginning with the calendar year in which he first
     participated in the Informatics Plan and ending on the later of the
     Participant's Normal Retirement Date or his Postponed Retirement Date.

     For purposes of this Section, (1) the term "Applicable Rate" means an
     annual rate of interest equal to:

      (a)  for periods prior to January 1, 1990, the rate credited to
           contributions under the Informatics Plan for such years, and

      (b)  for periods after December 31, 1989, the average rate of return
           credited for each completed calendar year under the fixed income
           investment option of the Sterling Software, Inc. Savings and Security
           (401k) Plan with the highest quality rating (excluding cash
           equivalents or money marked options). The Applicable Rate for the
           calendar year in which retirement occurs shall be the annual rate of
           interest on

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           30-year Treasury securities for the month of November preceding such
           calendar year.

      (2) the term "Compensation" means the Participant's taxable wages as
      reported on Form W-2 up to any limit under Section 401(a)(17) of the Code
      or any successor provision; and (3) all annuity amounts will be determined
      by using the annual rate of interest on 30-year Treasury securities for
      the month of November preceding the calendar year in which benefit
      payments begin and the applicable mortality table as prescribed by the
      Secretary of the Treasury under Section 417(e)(3) of the Code or any
      successor provision.

3.2   The monthly benefit payable to the Participant if he retires on an Early
      Retirement Date will equal the benefit determined in Section 3.1, except
      that the 50% multiplier described in Section 3.1(ii) will be multiplied by
      a fraction, the numerator of which is Service as of his Early Retirement
      Date and the denominator of which is his Service projected to his Normal
      Retirement Date. For example, if the Participant was 35 when hired and
      retired early at age 55, his annual benefit would be determined as the
      lessor of (i) or (ii), where

      (i)    is equal to 1/6 of 1% times months of Service at Early Retirement
             Date times Monthly Earnings at Early Retirement Date; and

      (ii)   is equal to 33-1/3% of Monthly Earnings less the Basic Plan
             Benefit;

      where 33-1/3% is equal to 50% multiplied by the fraction 240/360; and
      where 240 is his Service to age 55 and 360 is the service he would have
      had if he had continued to work to age 65, his Normal Retirement Date. The
      monthly benefit determined under this Section 3.2 will become payable on
      the Participant's Normal Retirement Date. For purposes of determining the
      Basic Plan Benefit under this section, all amounts to be determined under
      paragraphs (a), (b) and (c) of Section 3.1 shall be determined as of the
      Participant's Early Retirement Date. At the Committee's discretion,
      payments may begin any time after the Participant's Early Retirement Date
      and prior to his Normal Retirement Date and such monthly benefit shall be
      actuarially reduced based on the interest and mortality assumptions
      contained in clause (3) of the last sentence of Section 3.1.

3.3   The monthly benefit payable at a Postponed Retirement Date will be equal
      to the monthly benefit determined in accordance with Section 3.1 based on
      Service, Earnings, and the Participant's Basic Plan Benefit, as of the
      Participant's Postponed Retirement Date.

3.4   If the Participant becomes disabled and if he receives long-term
      disability benefits from the Company's Long-Term Disability Plan, the
      monthly benefit payable at Normal Retirement Date to the Participant under
      this Plan will be equal to the monthly benefit determined in accordance
      with Section 3.1 based on Service to Normal Retirement Date and Earnings
      and the Participant's Basic Plan Benefit as of the Participant's date of
      disability.

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3.5   The monthly benefit payable at a Disability Retirement Date will be equal
      to 66-2/3% of the Participant's Monthly Earnings as of his Disability
      Retirement Date, in excess of $7,500. Such benefit, payable monthly, shall
      commence on the date the Participant begins receiving a long-term
      disability benefit from the Company's Long-Term Disability Plan and will
      be payable as long as the Participant continues to receive a long-term
      disability benefit from such plan. Benefits from this Plan, payable as a
      result of a disability, will stop when benefits from the Long-Term
      Disability Plan cease. At age 65, benefits will commence in accordance
      with Section 3.4.

3.6   The benefits payable under the Plan, as determined in accordance with the
      appropriate preceding section of this Section III, except those determined
      in accordance with Section 3.5, will be payable in equal monthly
      installments, adjusted if appropriate as provided in Section 3.7, during
      the Participant's lifetime with benefits ceasing upon the Participant's
      death; however, if, at the time of the Participant's death, he has a
      Surviving Spouse, such Surviving Spouse shall receive a benefit equal to
      50% of the Participant's benefit as so adjusted, commencing on the first
      day of the month following the later of the month in which the surviving
      Spouse reaches age 55 or the month in which the Participant dies with such
      payments continuing to the death of the Surviving Spouse.

3.7   Any benefits payable hereunder, except those determined in Section 3.5,
      shall be adjusted upward annually, effective each March 1, beginning with
      the March 1 occurring at least 12 months after entitlement to benefit
      payments first occurs, to the extent that the CPI for the preceding
      calendar year exceeds a 5% increase from the next preceding calendar year.
      Any benefits payable hereunder shall be adjusted downward annually,
      effective each March 1, beginning with the March 1 occurring at least 12
      months after entitlement to benefit payments first occurs, to the extent
      that any decrease in the CPI for the preceding calendar year over the CPI
      for the next preceding calendar year exceeds 5%; provided, however, that,
      in no event shall the Participant's monthly benefit be less than the
      monthly benefit paid to him during the first month after entitlement to
      benefit payments first occurs.

3.8   To the extent that the Participant's employment is terminated in a manner
      that entitles him to severance benefits under the provisions of the
      Severance Agreement, (a) his benefit under this Plan shall be calculated
      by giving the Participant credit as Service for the number of months for
      which the Participant is entitled to severance benefits pursuant to the
      terms of the Severance Agreement; and (b) any severance benefits to which
      the Participant is entitled pursuant to the terms of the Severance
      Agreement shall not be included in the calculation of "Earnings."

                                  SECTION IV
                                  ----------
                        Payment of Retirement Benefits
                        ------------------------------

4.1   Benefits payable in accordance with Section III, except Section 3.5, will
      commence on the Participant's Normal or Postponed Retirement Date or upon
      a date determined by the Committee in accordance with Section 3.2. The
      last payment will be on the first day of

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      the month in which the Participant dies unless he has a Surviving Spouse
      in accordance with Section 3.6.

                                   SECTION V
                                   ---------
                            Death Benefits Payable
                            ----------------------

5.1   If the Participant dies before Retirement, excluding Disability
      Retirement, his Surviving Spouse will receive a monthly benefit equal to
      50% of the amount of the Participant's monthly benefit determined in
      accordance with Section 3.1 as if the Participant had retired and
      commenced receiving a benefit on the first day of the month following the
      date of his death.

5.2   A surviving Spouse's benefits will be payable monthly, and will commence
      on the first day of the month following the later of the month in which
      the Surviving Spouse reaches age 55 or the month in which the Participant
      dies. The last payment will be on the first day of the month in which the
      Surviving Spouse dies. Cost of living adjustments determined as described
      in Section 3.7 will apply to a Surviving Spouse's benefits.

                                  SECTION VI
                                  ----------
                                 Miscellaneous
                                 -------------

6.1   Nothing contained herein will confer upon the Participant the right to be
      retained in the service of the Company, nor will it interfere with the
      right of the Company to discharge or otherwise deal with the Participant
      without regard to the existence of this Plan.

6.2   This Plan is unfunded, and the Company will make Plan benefit payments
      solely on a current disbursement basis.

6.3   To the maximum extent permitted by law, no benefit under this Plan shall
      be assignable or subject in any manner to alienation, sale, transfer,
      claims of creditors, pledge, attachment, or encumbrance of any kind.

6.4   The Committee may adopt rules and regulations to assist it in the
      administration of the Plan.

6.5   The Participant shall receive a copy of this Plan.

6.6   The Plan will be construed and governed in all respects in accordance with
      applicable federal law and, to the extent not preempted by such federal
      law, in accordance with the laws of the State of Texas, including without
      limitation, the Texas statute of limitations, but without giving effect to
      the principles of conflicts of laws of such State.

6.7   Subject to the following provisions of this Section 6.7, this Plan may be
      terminated or from time to time amended by the Committee in its
      discretion. Notwithstanding the preceding sentence or any other provision
      herein to the contrary, (a) this Plan may not be terminated or

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      amended if such termination or amendment would reduce or adversely affect
      benefits previously accrued hereunder, and (b) from and after the date of
      a Change in Control (as that term is defined below), this Plan may not be
      terminated or amended in any manner that could reasonably be expected to
      have an adverse effect on the Participant or his Surviving Spouse, without
      the prior written consent of the Participant or such Surviving Spouse. As
      used herein, the term "Change in Control" shall mean the occurrence of any
      of the following events:

                 (i)    The Company is merged, consolidated or reorganized into
           or with another corporation or other legal person, and as a result of
           such merger, consolidation or reorganization less than two-thirds of
           the combined voting power of the then-outstanding securities entitled
           to vote generally in the election of directors ("Voting Stock") of
           such corporation or person immediately after such transaction are
           held in the aggregate by the holders of Voting Stock of the Company
           immediately prior to such transaction;

                 (ii)   The Company sells or otherwise transfers all or
           substantially all of its assets to another corporation or other legal
           person, and less than two-thirds of the combined voting power of the
           then-outstanding Voting Stock of such corporation or person is held
           in the aggregate by the holders of Voting Stock of the Company
           immediately prior to such sale or transfer;

                 (iii)  There is a report filed on Schedule 13D or Schedule 14D-
           1 (or any successor schedule, form or report), each as promulgated
           pursuant to the Securities Exchange Act of 1934, as amended (the
           "Exchange Act"), disclosing that any person (as the term "person" is
           used in Section 13(d)(3) or Section 14(d)(2) of the Exchange Act) has
           become the beneficial owner (as the term "beneficial owner" is
           defined under Rule 13d-3 or any successor rule or regulation
           promulgated under the Exchange Act) of securities representing 20% or
           more of the combined voting power of the then-outstanding Voting
           Stock of the Company;

                 (iv)   The Company files a report or proxy statement with the
           Securities and Exchange Commission pursuant to the Exchange Act
           disclosing in response to Form 8-K or Schedule 14A (or any successor
           schedule, form or report or item therein) that a change in control of
           the Company has occurred or will occur in the future pursuant to any
           then-existing contract or transaction; or

                 (v)    If, at any time during any period of two consecutive
           years, individuals who at the beginning of any such period constitute
           the directors of the Company cease for any reason to constitute at
           least a majority thereof; provided, however, that for purposes of
           this clause (v) each director (other than a director whose initial
           assumption of office is in connection with an actual or threatened
           election contest) who is first elected, or first nominated for
           election by the Company's stockholders, by a vote of at least two-
           thirds of the directors of the Company (or a committee thereof) then
           still in office who were directors of the Company at the beginning of
           any such period will be deemed to have been a director of the Company
           at the beginning of such period.

      Notwithstanding the foregoing provisions of clauses (iii) or (iv), unless
      otherwise determined in

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      a specific case by majority vote of the board of directors of the Company,
      a "Change in Control" shall not be deemed to have occurred for purposes of
      clause (iii) or (iv) solely because (A) the Company, (B) an entity in
      which the Company directly or indirectly beneficially owns 50% or more of
      the outstanding Voting Stock (a "Subsidiary"), or (C) any Company-
      sponsored employee stock ownership plan or any other employee benefit plan
      of the Company or any Subsidiary either files or becomes obligated to file
      a report or a proxy statement under or in response to Schedule 13D,
      Schedule 14D-1, Form 8-K or Schedule 14A (or any successor schedule, form
      or report or item therein) under the Exchange Act disclosing beneficial
      ownership by it of shares of Voting Stock of the Company, whether in
      excess of 20% or otherwise, or because the Company reports that a change
      in control of the Company has occurred or will occur in the future by
      reason of such beneficial ownership or any increase or decrease thereof.

                                       STERLING SOFTWARE, INC.



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

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