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                                                                   Exhibit 10(f)



                  SCIENCE APPLICATIONS INTERNATIONAL CORPORATION

                             KEYSTAFF DEFERRAL PLAN


                           (Effective January 1, 1997)


                                (Amended 01/03/01)

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                             KEYSTAFF DEFERRAL PLAN

                                       OF

                 SCIENCE APPLICATIONS INTERNATIONAL CORPORATION


1.     Purpose

       1.1      The purpose of this Plan is to provide a means to enhance the
                Company's capacity to attract and retain outstanding directors
                and executives in key positions by assisting them in meeting
                their future financial security objectives.

2.     Definitions

       2.1      Whenever the following terms are used in this document and the
                attached Plan Agreement, they shall have the meaning specified
                below.

       2.2      "Deferral Account" shall mean a bookkeeping account established
                by the Company for each Participant, in which shall be recorded
                the amounts deferred in accordance with this Plan and the
                attached Agreement. The Company shall credit to each
                Participant's Deferral Account an amount equal to the
                compensation which otherwise would have been paid had the
                Participant not elected to defer compensation. Such credits
                shall be made at the time compensation would have been paid to
                the Participant. The Deferral Account shall also receive
                quarterly earnings credits in accordance with provisions of
                Section 5.

                Separate Deferral Accounts shall be established to record
                amounts deferred (and earnings credits thereon) with respect to
                Plan Years beginning before and after December 31, 1990, to be
                referred to herein as Pre-1991 Deferral Accounts and Post-1990
                Deferral Accounts, respectively. Except as otherwise stated
                herein, references to Deferral Account(s) shall include both the
                Pre-1991 and Post-1990 Deferral Account(s).

       2.3      "Anniversary Date" shall be the last day of a Plan Year.

       2.4      "Beneficiary" shall mean the person or persons, or the estate of
                a Participant, entitled to receive any benefits under this Plan
                upon the death of a Participant.

       2.5      "Ceiling Excess Earnings" shall mean, for each Pre-1991 Deferral
                Account, the difference between the Participant's Pre-1991
                Deferral Account if interest had been credited at a rate of
                Moody's plus 5% in each Plan Year and the Participant's actual
                current Pre-1991 Deferral Account.


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                A separate calculation of Ceiling Excess Earnings shall be made
                with respect to post-1990 Deferral Account(s) using a rate of
                Moody's plus 3%.

       2.6      "Commitment Period" shall mean that period of time beginning
                with the subsequent Plan Year and extending for a number of Plan
                Years as determined from time to time by the Committee.

       2.7      "Covered Compensation" shall mean a Director's compensation, as
                a Director of the Company, excluding expenses reimbursed, or an
                Executive's merit bonus in each Plan Year. The Committee, in its
                sole discretion, shall determine what constitutes a merit bonus.

       2.8      "Committee" shall mean the administrative Committee appointed to
                manage and administer the Plan in accordance with the provisions
                of this Plan.

       2.9      "Company" shall mean SCIENCE APPLICATIONS INTERNATIONAL
                CORPORATION, its subsidiaries, or any successor.

       2.10     "Director" shall mean any person not in regular full-time
                employment of the Company serving on the Board of Directors of
                Science Applications International Corporation or any
                subsidiary or affiliate of Science Applications International
                Corporation.

       2.11     "Early Retirement Date" shall mean the date that the Participant
                attains his or her fifty-fifth (55th) birthday.

       2.12     "Effective Date" shall be January 1, 1986.

       2.13     "Employer" shall mean the Company and any subsidiary having one
                or more employees who are eligible to participate in the Plan
                and have been selected by the Committee to participate. Where
                the context dictates, the term "Employer" as used herein refers
                to the particular Employer which has entered into a Plan
                Agreement with a specific Participant.

       2.14     "Executive" shall mean any person in the employment of the
                Company who is determined by the Committee to be serving in an
                executive capacity, excluding those persons meeting the
                definition set forth in Section 2.10.

       2.15     "Master Plan Document" is this legal instrument containing the
                provisions of the Plan.

       2.16     "Moody's Seasoned Corporate Bond Rate," sometimes referred to as
                "Moody's," is an economic indicator; an arithmetic average of
                yields of representative bonds: industrials, public utilities,
                AAA, AA, A and BAA. For Plan purposes, Moody's


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                Rate shall be determined by the Committee based on financial
                services or publications selected by the Committee.

       2.17     "Normal Retirement Date" shall mean the date that the
                Participant attains his or her sixty-fifth (65th) birthday.

       2.18     "Participant" shall mean any Executive or Director who elects to
                participate in the Keystaff Deferral Plan, signs a Plan
                Agreement, and is accepted into the Plan.

       2.19     "Plan" shall mean the Keystaff Deferral Plan of the Employer
                which shall be evidenced by this instrument and by each Plan
                Agreement.

       2.20     "Plan Agreement" shall mean the written agreement(s) entered
                into from time to time by and between an Employer and a
                Participant. A separate Plan Agreement shall be entered into
                with respect to the Pre-1991 Deferral Account and Post-1990
                Deferral Account of a Participant.

       2.21     "Plan Year" shall begin on January 1 of each year.

       2.22     "Retirement" and "Retire" shall mean severance from employment
                with the Employer at or after the attainment of (i) age
                fifty-five (55) and ten (10) years of Plan participation or (ii)
                age sixty-five (65). The Committee shall have the sole
                discretion to determine whether Retirement has occurred in the
                case of an Executive who becomes a consulting employee or who
                continues to be affiliated with the Company as a consultant or
                under some other status.

       2.23     "Termination of Employment" shall mean cessation of regular
                employment, voluntarily or involuntarily, but excluding
                Retirement or death, as determined by the Committee in its sole
                discretion. In the case of a Director, "Termination of
                Employment" shall mean the Director's ceasing to be a Director
                of the Company. The Committee shall have the sole discretion to
                determine (i) whether a change in status (e.g., from employee to
                consultant, from employee to consulting employee, or from
                director to employee, consulting employee or consultant) shall
                be considered a Termination of Employment, (ii) whether a leave
                of absence shall be considered a Termination of Employment, and
                (iii) when a consultant or consulting employee will be
                considered to have a Termination of Employment.

3.     Eligibility

       3.1      The Committee will determine which Executives and Directors of
                the Company are eligible to participate in the Plan.

4.     Deferral Commitments

       4.1      Deferral Elections


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                Each Executive and Director who wishes to participate in the
                Plan must elect, prior to the first Plan Year of the
                Participant's eligibility, to defer during each year of the
                Commitment Period a fixed percentage of the Participant's
                Covered Compensation. This election will be irrevocable and
                binding upon the Participant, except as provided in Section 4.2,
                "Changes to Deferral Elections." Participants may elect to defer
                up to 100% but not less than 10% of Covered Compensation, in
                whole percentages, but not less than $1,000 (before reductions,
                if any, under Section 4.2.1).

                With respect to the Post-1990 Deferral Account elections, the
                Committee shall specify annual election periods during which
                irrevocable deferral elections by Participants shall be made.

       4.2      Changes to Deferral Elections

       4.2.1    The maximum allowable total deferral of Covered Compensation for
                all Participants under this Plan for any Plan Year will be
                determined by the Committee. In the event that Participant
                deferral elections are estimated to result in this maximum being
                exceeded, the following method will be used to reduce
                Participant deferral percentages so that the total estimated
                deferral is less than the maximum allowable.

                a)    All Executives who have elected to defer more than 50% of
                      Covered Compensation will be reduced, on an equal
                      percentage basis, but not below 50% of Covered
                      Compensation or $5,000, whichever is greater.

                b)    If after implementation of subsection (a) above, the total
                      deferral is still greater than the maximum allowable total
                      deferral, all Executives' percentage deferrals will be
                      reduced on an equal percentage basis until the maximum
                      allowable total deferral is achieved.

       4.2.2    In the event that a Participant rescinds, in whole or in part,
                his or her election to defer a percentage of Covered
                Compensation in any Plan Year, the Participant may not defer any
                Covered Compensation for the balance of the Plan Year, nor in
                the following Plan Year.

       4.2.3    The Committee, in its sole discretion, may elect to terminate
                the Plan at any time pursuant to Section 9; in such event,
                deferrals will cease effective as of the termination date.

       4.3      Rollover of Balances from Current Deferred Compensation Plan



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       4.3.1    Participants who hold a balance in the Company's current
                Deferred Compensation Plan may elect to transfer that balance on
                a bookkeeping basis into this Plan at the beginning of the first
                Plan Year.

5.     Earnings on Participants' Accounts

       5.1      Base Earnings on Deferral

       5.1.1    Covered Compensation deferred by a Participant shall be credited
                to the Participant's Deferral Account as of the date of
                deferral. Interest in each Plan Year will be credited quarterly
                on the average Deferral Account balance for that quarter. The
                rate of interest applied to the Pre-1991 Deferral Account shall
                be at a base rate equivalent to an annual rate equal to Moody's
                Rate, and the rate applicable to the Post-1990 Deferral Account
                shall be at a base rate equivalent to an annual rate equal to
                the Moody's Rate less 1%. In each case, the Moody's Rate in
                effect on each Anniversary Date shall be used to determine the
                applicable rate of interest applied during the subsequent Plan
                Year.

       5.2      Earnings on Rollover Balances

       5.2.1    The portion of a Participant's Pre-1991 Deferral Account
                resulting from the transfer of a balance from the Company's
                current Deferred Compensation Plan will be credited quarterly
                with a rate of interest equivalent to 60% of the interest rate
                announced by Bank of America as its "prime rate" on the previous
                Anniversary Date for the first four (4) Plan Years. After the
                fourth Plan Anniversary Date, this portion of the Pre-1991
                Deferral Account will be credited with interest quarterly at an
                effective annual rate equal to Moody's Rate plus 9% until the
                cumulative interest equals that amount of interest which would
                have been credited assuming that Moody's Rate had been used
                since Plan inception. At that time, the distinction between
                portions of the Pre-1991 Deferral Account from deferrals and
                from transfers will cease to exist.

       5.3      Additional Earnings

       5.3.1    The Committee may, in its sole discretion, determine whether and
                in what amount additional earnings shall be allocated to
                Participants' Deferral Accounts. It is anticipated, but not
                guaranteed, that for Pre-1991 Deferral Accounts, additional
                earnings will be allocated beginning with the 10th Anniversary
                Date of the Plan and that for Post-1990 Deferral Accounts,
                additional earnings will be allocated beginning on January 1,
                2001. Whether additional earnings will be credited and their
                amount will depend upon several factors, including the Company's
                future tax rate and its after-tax return on investments.
                Additional earnings in any Plan Year, if any, as determined by
                the Committee, will be allocated to each Participant's Deferral
                Account (except as otherwise provided in Section 6.1.3 and
                except for Deferral Accounts of Participants who have had a
                Termination of



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                Employment prior to ten years of participation in the Plan) by
                the ratio of the Participant's Ceiling Excess Earnings to the
                sum of all Participants' Ceiling Excess Earnings as of the end
                of the Plan Year, with such additional earnings and Ceiling
                Excess Earnings calculated separately for Pre-1991 and Post-1990
                Deferral Accounts.

6.     Payout of Participants' Accounts

       6.1      Early Withdrawal Option

       6.1.1    Participants may elect a one-time early withdrawal of up to 75%
                of their Pre- 1991 and/or Post-1990 Deferral Account(s) to be
                paid within 90 days following any Anniversary Date starting with
                the seventh Anniversary Date of Plan participation.

       6.1.2    Participants shall make an annual election prior to each
                Anniversary Date starting with the 6th Anniversary Date whether
                to continue their deferral for one or more years or to receive
                the early withdrawal payment following the subsequent
                Anniversary Date.

       6.1.3    Participants who elect the one-time early withdrawal of up to
                75% of their Pre- 1991 and/or Post-1990 Deferral Account(s)
                pursuant to this Section 6.1 shall not be entitled to receive
                additional earnings, if any, otherwise allocable under Section
                5.3.1 to the remaining portion of their applicable Deferral
                Account(s) from which the withdrawal is made.

       6.2      Termination Payouts

       6.2.1    A Participant who has a Termination of Employment prior to one
                year of Plan Participation shall receive an amount equal to his
                or her Deferral Account, less any credited earnings. Payment
                shall be make in a lump sum within twelve months following
                Termination of Employment.

       6.2.2    A Participant who has a Termination of Employment after one year
                of Plan Participation but prior to 10 years of Plan
                participation shall receive payment in a lump sum within twelve
                months following Termination of Employment equal to his or her
                Deferral Account(s) as of the most recent quarterly valuation.

       6.2.3    A Participant who has a Termination of Employment after 10 years
                of Plan participation shall be subject and entitled to the
                Normal Payout provisions set forth in Section 6.4.

       6.3      Survivor Payouts



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       6.3.1    If a Participant dies before Normal Payout commences and the
                Plan Agreement is in effect at the time of death, the Employer
                shall make a Survivor Payout, as defined in Section 6.3.2, to
                the designated Beneficiary.

       6.3.2    The Survivor Payout shall consist of the Participant's Deferral
                Account(s) at the time of death.

       6.3.3    The Survivor Payout shall be paid in a lump sum to the
                Beneficiary within twelve months following verification of the
                Participant's death.

       6.3.4    Notwithstanding subsection 6.3.3 above, a Participant may elect
                on the Beneficiary form provided by the Committee that the
                Survivor Payout be made over a 20-, 40-, or 60-quarter period
                rather than as a lump sum.

       6.4      Normal Payouts

       6.4.1    Normal Payouts shall commence at age sixty-five (65), Retirement
                or ten (10) years of Plan participation, whichever is the latest
                to occur.

       6.4.2    A Participant who Retires may request that Normal Payout
                commence upon such Retirement. The Committee in its sole
                discretion may grant such request in the event that the
                Participant demonstrates financial need and the cash flow of the
                Company permits such early commencement.

       6.4.3    The Participant shall elect to receive the Normal Payout over a
                20-, 40- or 60- quarter period. The first payment will commence
                within 90 days of the quarter end following Retirement.

       6.4.4    If a Participant does not elect a payout option, the payments
                shall be over a 20- quarter period.

       6.4.5    Normal Payout shall consist of the Participant's Deferral
                Account(s) spread equally over the elected payout period.
                Earnings, and additional earnings, if applicable, as provided in
                Subsection 5.3.1, shall continue to be credited to the remaining
                Deferral Account(s) during the payout period and shall be
                estimated so that approximately equal payments can be made.

       6.4.6    If a Participant dies during the Normal Payout period, Normal
                Payout shall continue as scheduled to the Participant's
                Beneficiary.

       6.4.7    The election provided in Section 6.4.3 shall be made during the
                initial Commitment Period of Plan participation and shall become
                irrevocable at the end of such period.

       6.5      Payment for Notification of Death



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       6.5.1    If a Participant dies following either Retirement or Termination
                of Employment, the Company will pay a $5,000 notification
                payment of a lump sum to the Participant's Beneficiary within 90
                days of the quarter end following verification of the
                Participant's death.

7.     Beneficiary Designation

       7.1      Upon forms provided by the Committee, each Participant shall
                designate in writing the Beneficiary or Beneficiaries whom such
                Participant desires to receive the benefits of this Plan,
                payable under Sections 6.3, 6.4 and/or 6.5, in the event of such
                Participant's death.

       7.2      A Participant may from time to time change his or her designated
                Beneficiary or Beneficiaries without the consent of such
                Beneficiary or Beneficiaries by filing a new designation in
                writing with the Committee.

       7.3      If a married Participant wishes to designate an individual other
                than his or her spouse as Beneficiary, such designation shall
                not be effective (i.e., the surviving spouse shall be treated as
                the sole Beneficiary) unless consented to in writing by the
                spouse, which consent shall acknowledge the effect of the
                designation and be witnessed by a member of the Committee (or an
                individual designated by the Committee) or acknowledged before a
                notary public. Notwithstanding the foregoing, spousal consent
                shall not be necessary if it is established to the satisfaction
                of the Committee that there is no spouse of the Participant or
                that the required consent cannot be obtained because the spouse
                cannot be located. The Company may rely upon the designation of
                Beneficiary or Beneficiaries last filed by the Participant in
                accordance with the terms of this Plan.

       7.4      If the designated Beneficiary does not survive the Participant,
                or if there is no valid Beneficiary designation, amounts payable
                under the Plan shall be paid to the Participant's spouse, or if
                there is no surviving spouse, then to the duly appointed and
                currently acting personal representative of the Participant's
                estate. If there is no personal representative of the
                Participant's estate duly appointed and acting in that capacity
                within 60 days after the Participant's death, then all payments
                due under the Plan shall be payable to the person or persons who
                can verify affidavit or court order to the satisfaction of the
                Committee that they are legally entitled to receive the benefits
                specified hereunder pursuant to the laws of interstate
                succession or other statutory provision in effect at the
                Participant's death in the state in which the Participant
                resided.

       7.5      In the event any amount is payable under the Plan to a minor,
                payment shall not be made to the minor, but instead shall be
                paid to that person's then living parent(s) to act as custodian,
                or, if no parent of that person is living, to a custodian
                selected by the Committee to hold the funds for the minor under
                the



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                Uniform Transfers to Minors Act, or similar law, in effect in
                the jurisdiction in which the minor resides.

8.     Acceleration Provisions

       8.1      Notwithstanding the provisions of Section 6 hereof, a
                Participant shall be entitled to request a hardship withdrawal
                of all or any portion of their Deferral Account or acceleration
                of payments of their Deferral Account if payments have already
                commenced under the payout option selected by the Participant. A
                Participant must make a written request to the Committee for a
                hardship withdrawal or request for accelerated payment, stating
                the reasons such withdrawal or acceleration is necessary because
                of a financial hardship. The Committee, in its sole discretion,
                shall determine whether or not to grant the Participant's
                request and, in so doing, may rely on the Participant's
                statements, and a hardship withdrawal or accelerated payment may
                be approved without further investigation unless the Committee
                has reason to believe such statements are false.

                The Participant shall specify from which of their Deferral
                Account(s) (i.e., Pre- 1991 or Post-1990, or both) the hardship
                withdrawal shall be taken.

       8.2      The Committee, acting in its sole discretion, may determine to
                accelerate, in whole or in part, payments of some or all
                Deferral Account(s) (including Deferral Account(s) as to which
                payments have not yet commenced) in the event of a threatened or
                actual change in control of the Company, or in the event that a
                change in the legal, accounting, or tax treatment of amounts
                deferred under the Plan are altered in a manner which would
                potentially subject the Company, the Participants, or both, to
                adverse tax or administrative burdens.

9.     Amendment and Termination of Plan

       9.1      The Company may, at its absolute and sole discretion, amend or
                terminate the Plan at any time.

       9.2      In the event of Company-initiated Plan termination,
                Participants' entire Deferral Account(s), including credited
                interest, will be paid to Participants within twelve months of
                the quarter end following Plan termination.

10.    Nature of Accounts

       10.1     All amounts credited to the Deferral Account(s) shall remain the
                sole property of the Company and shall be usable by it as part
                of its general funds for any legal purpose whatsoever. The
                Deferral Account(s) shall exist only as bookkeeping entries for
                the purpose of facilitating the computation of earnings credits
                hereunder and such Deferral Account(s) shall not constitute
                trust funds, escrow accounts, or any other form of asset
                segregation in favor of anyone other than the



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                Company. No participant shall have any interest in any specific
                asset of the Company by virtue of this Plan and each
                Participant's rights under this Plan shall at all times be
                limited to those of a general unsecured creditor of the Company.

                Although sometimes referred to in this Plan as "interest,"
                amounts credited to Deferral Account(s) pursuant to Section 5.1,
                5.2 and 5.3 may be treated as compensation for tax and payroll
                withholding purposes, pursuant to applicable Internal Revenue
                Code and Treasury regulation requirements.

11.    Limitation on Rights of Participants

       11.1     If a Participant is an employee of the Company, such employment
                is not for any specific term and may be terminated by the
                Participant or Company at any time, for any reason, with or
                without cause. Neither this Plan nor any election to defer
                compensation hereunder shall be held or construed to confer on
                any person any legal right to be continued as an employee,
                consultant or Director of the Company; nor to constitute any
                promise or commitment by the Company regarding future positions,
                future work assignments, future compensation or any other term
                or condition of employment or affiliation.

12.    Non-Transferability

       12.1     No right to payment under this Plan shall be subject to
                anticipation, alienation, sale, assignment, pledge, encumbrance,
                or charge and any attempt to anticipate, alienate, sell, assign,
                pledge, encumber, or charge the same shall be void. No right to
                payment shall in any manner be liable for, or subject to, the
                debts, contracts, liabilities or torts of the person entitled
                thereto.

13.    Restriction Against Assignment

       13.1     The Participant or Beneficiary shall not have the power to
                transfer, assign, anticipate, modify, or otherwise encumber in
                any manner whatsoever any of the payments that will become due
                pursuant to this Plan, nor shall said payments be subject to
                attachment, garnishment or execution, or be transferable by
                operation of law in event of bankruptcy or insolvency.

14.    Binding Effect

       14.1     The Plan Agreement or Agreements attached hereto, when executed,
                is/are solely between the Company and the Participant. The
                Participant and any Beneficiary shall have recourse only against
                the Company for its enforcement, and any Plan Agreement shall be
                binding upon the Beneficiary, heirs, and personal representative
                of the Participant and upon the successors and assigns of the
                Company.



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15.    Settlement of Disputes

       15.1     If any disputes arise with regard to the interpretation of any
                of the provisions of this Plan or with regard to the amount of
                any payments due under this Plan and the Agreement, the
                Committee shall make any resolution of such disputes which it
                deems, in its sole discretion, to be in the best interest of the
                Company and the Participants. Any such determinations made by
                the Committee shall be final and binding on all Participants in
                the Plan.

       15.2     The Committee shall adopt procedures, consistent with Section
                503 of the Employee Retirement Income Security Act of 1974, with
                respect to notice to Participants of claims denied under the
                Plan and review of denied claims.

16.    Administration

       16.1     The Plan shall be administered by the Committee, as appointed by
                the President of the Company.

17.    Forfeiture

       Any payment due to a Participant hereunder which is not claimed by the
       Participant, his or her Beneficiary, his or her estate or other person
       legally entitled thereto within four years after becoming payable shall
       be forfeited and canceled and shall remain with the Company and no other
       person shall have any right thereto or interest therein. The Company
       shall have no duty under this Agreement to give notice to any person
       other than the Participant or his or her designated Beneficiary that
       amounts are payable hereunder.



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