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Exhibit 10.13

                         EXECUTIVE EMPLOYMENT AGREEMENT

      This Employment Agreement (this "Agreement") is made as of November 1,
2004 (the "Effective Date"), by and between BMC Software, Inc., a Delaware
corporation (the "Employer"), and Mr. Cosmo Santullo (the "Executive"). The
Employer and the Executive are each a "party" and are together "parties" to this
Agreement.

                                    RECITALS

      WHEREAS, the Employer desires to employ the Executive, and the Executive
wishes to accept such employment, upon the terms and conditions set forth in
this Agreement.

                                    AGREEMENT

      NOW THEREFORE, in consideration of the employment compensation to be paid
to the Executive and other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties, intending to be
legally bound, agree as follows:

1. DEFINITIONS

      For the purposes of this Agreement, the following terms have the meanings
specified or referred to in this Section 1.

      "AGREEMENT" refers to this Employment Agreement, including all Exhibits
attached hereto, as amended from time to time.

      "BENEFITS" as defined in Section 3.1(b).

      "BOARD OF DIRECTORS" refers to the board of directors of the Employer.

      "CHANGE OF CONTROL" refers to (i) the acquisition of at least 50% of
Employer's outstanding voting stock; (ii) an unapproved change in the majority
of the Employer's board of directors; (iii) a merger, consolidation, or similar
corporate transaction in which the Company's shareholders immediately prior to
the transaction do not own more than 60% of the voting stock of the surviving
corporation in the transaction; and (iv) shareholder approval of the company's
liquidation, dissolution, or sale or substantially all of its assets.

      "CONFIDENTIAL INFORMATION" means any and all:

            a. trade secrets (as defined herein) concerning the business and
      affairs of the Employer, product specifications, data, know-how, formulae,
      compositions, processes,

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      designs, sketches, photographs, graphs, drawings, samples, inventions and
      ideas, past, current, and planned research and development, current and
      planned manufacturing or distribution methods and processes, customer
      lists, current and anticipated customer requirements, price lists, market
      studies, business plans, computer software and programs (including object
      code and source code), computer software and database technologies,
      systems, structures, and architectures (and related formulae,
      compositions, processes, improvements, devices, know-how, inventions,
      discoveries, concepts, ideas, designs, methods and information), and any
      other information, however documented, that is a trade secret;

            b. information concerning the business and affairs of the Employer
      (which includes historical financial statements, financial projections and
      budgets, historical and projected sales, capital spending budgets and
      plans, the names and backgrounds of key personnel, personnel training and
      techniques and materials), however documented; and

            c. notes, analysis, compilations, studies, summaries, and other
      material prepared by or for the Employer containing or based, in whole or
      in part, on any information included in the foregoing.

      "DISABILITY" as defined in Section 6.2.

      "EFFECTIVE DATE" is the date stated in the first paragraph of the
Agreement.

      "EMPLOYEE INVENTION" shall mean any idea, invention, technique,
modification, process, or improvement (whether patentable or not), any
industrial design (whether registerable or not), any mask work, however fixed or
encoded, that is suitable to be fixed, embedded or programmed in a semiconductor
product (whether recordable or not), and any work of authorship (whether or not
copyright protection may be obtained for it) created, conceived, or developed by
the Executive, either solely or in conjunction with others, during the
Employment Period, or a period that includes a portion of the Employment Period,
that relates in any way to, or is useful in any manner in, the business then
being conducted or proposed to be conducted by the Employer, and any such item
created by the Executive, either solely or in conjunction with others, following
termination of the Executive's employment with the Employer, that is based upon
or uses Confidential Information.

      "EMPLOYMENT PERIOD" is the term of the Executive's employment under this
Agreement.

      "FISCAL YEAR" shall mean the Employer's fiscal year, which shall end on
March 31 of each year, or as changed from time to time.

      "FOR CAUSE" as defined in Section 6.3.

      "GOOD REASON" as defined in Section 6.3.

      "PERSON" is any individual, corporation (including any non-profit
corporation), general or limited partnership, limited liability company, joint
venture, estate, trust, association, organization,

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or governmental body.

      "PROPRIETARY ITEMS" as defined in Section 7.2(a)(iv).

      "SALARY" as defined in Section 3.1(a).

      "TRADE SECRETS" shall mean the whole or any part of any scientific or
technical information, design, process, procedure, formula, or improvement that
has value and that the owner has taken measures to prevent from becoming
available to persons other than those selected by the owner to have access for
limited purposes.

2. EMPLOYMENT TERMS AND DUTIES

      2.1 EMPLOYMENT

      The Employer hereby employs the Executive, and the Executive hereby
accepts employment by the Employer, upon the terms and conditions set forth in
this Agreement.

      2.2 EMPLOYMENT PERIOD

      Subject to the provisions of Section 6, the term of the Executive's
employment under this Agreement will commence upon the Effective Date and shall
continue in effect through the third anniversary of the Effective Date (the
"Employment Period"); provided, however, that, subject to the provisions of
Section 6, commencing on the day after the Effective Date and on each day
thereafter, the Employment Period shall be automatically extended for one
additional day unless the Employer shall give written notice to Executive that
the Employment Period shall cease to be so extended, in which event the
Employment Period shall terminate on the third anniversary of the date such
notice is given. The Employment Period may be further extended by mutual
agreement of the parties.

      2.3 DUTIES

      The Executive will have such duties as are assigned or delegated to the
Executive by the Chief Executive Officer, and will initially serve as the
Employer's SVP Worldwide Sales and Services. The Executive will devote his
entire business time, attention, skill, and energy exclusively to the business
of the Employer, will use his best efforts to promote the success of the
Employer's business, and will cooperate fully with the Chief Executive Officer
in the advancement of the best interests of the Employer. The Executive's
employment will be subject to the policies maintained and established by the
Employer, from time to time. Nothing in this Section 2.3, however, will prevent
the Executive from engaging in additional activities in connection with passive
personal investments and community affairs that are not inconsistent with the
Executive's duties under this Agreement. Additionally, nothing in this Section
2.3 will prevent the Executive from serving on the Board of Directors of other
companies or organizations, or engaging in other activities, so long as such
participation does not conflict with the interests or business of Employer or
require such involvement as to interfere with the performance of the Executive's
duties hereunder and has been

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expressly approved by the Chief Executive Officer of Employer. If the Executive
is elected as a director of the Employer or as a director or officer of any of
its affiliates, the Executive will fulfill his duties as such director or
officer without additional compensation. The Executive acknowledges and agrees
that he owes a fiduciary duty of loyalty, fidelity and allegiance to act at all
times in the best interests of the Employer.

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3. COMPENSATION

      3.1 COMPENSATION

            a. Salary. During the Employment Period, the Executive will be paid
      an annual base salary of $425,000 (the "Salary"), which will be payable in
      twenty-four (24) equal installments according to the Employer's customary
      payroll practices. Executive may be subject to such increases in Salary as
      deemed appropriate in the sole discretion of the Compensation Committee of
      the Board of Directors of Employer.

            b. Benefits. The Executive will, during the Employment Period, be
      permitted to participate in such pension, profit sharing, life insurance,
      hospitalization, major medical, and other employee benefit plans of the
      Employer that may be in effect from time to time, to the extent the
      Executive is eligible under the terms of those plans (collectively, the
      "Benefits").

            c. Stock Options. The Executive will be entitled to receive, subject
      to approval of the Compensation Committee, an option to purchase 250,000
      shares of common stock of the Employer. Such options will be subject to
      the terms and conditions of the BMC Software, Inc. 1994 Employee Incentive
      Plan and an Executive Stock Option Agreement and will have a strike price
      set on the Effective Date.

            d. Cash Bonus. Executive will be eligible for a cash bonus target
      equal to 150% of base salary as described in Attachment A incorporated
      herein by reference. Such bonus will be guaranteed at the target for the
      period from the Effective Date through December 31, 2004 (paid pro rata)
      and for the quarter ending March 31, 2005.

            e. Long Term Incentive Program. Executive will be eligible to
      participate in the Long Term Incentive Plan commencing at the beginning of
      the next Fiscal Year as approved by the BMC Board of Directors.

            f. Sign on Bonus. Executive will be paid a $50,000 bonus payable
      within the first 15 days of employment.

4. FACILITIES AND EXPENSES

      4.1 FACILITIES.

      The Employer will furnish the Executive office space, equipment, supplies,
and such other facilities and personnel as the Employer deems necessary or
appropriate for the performance of the Executive's duties under this Agreement.

      4.2 EXPENSES.

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      The Employer will pay on behalf of the Executive (or reimburse the
Executive for) reasonable expenses incurred by the Executive at the request of,
or on behalf of, the Employer in the performance of the Executive's duties
pursuant to this Agreement, and in accordance with the Employer's employment
policies, including reasonable expenses incurred by the Executive in attending
business meetings, in appropriate business entertainment activities, and for
promotional expenses. The Executive must file expense reports with respect to
such expenses in accordance with the Employer's policies then in effect.

5.    VACATIONS AND HOLIDAYS

      The Executive will be entitled to paid vacation during the term of the
Agreement in accordance with the vacation policies of the Employer in effect for
its employees from time to time. The Executive will also be entitled to the paid
holidays and other paid leave set forth in the Employer's policies.

6.    TERMINATION

      6.1 EVENTS OF TERMINATION

      The Employment Period, the Executive's Salary and any and all other rights
of the Executive under this Agreement or otherwise as an employee of the
Employer will terminate (except as otherwise provided in this Section 6):

            a. upon the death of the Executive;

            b. upon the Disability (as defined in Section 6.2) of the Executive
      immediately upon notice from either party to the other;

            c. upon termination by the Employer for cause (as defined in Section
      6.3);

            d. upon the voluntary retirement from or voluntary resignation of
      employment by the Executive for any reason other than those set forth in
      Section 6.1(f) below;

            e. upon termination by the Employer for any reason other than those
      set forth in Section 6.1(a) through 6.1(d) above; or

            f. upon voluntary resignation of employment by the Executive within
      60 days of the occurrence of an event that constitutes Good Reason, as
      defined in Section 6.3 below.

      Upon termination of the Employment Period, as provided above or otherwise,
Executive's rights respecting Benefits, Stock Options, and Cash Bonus will be
determined under the applicable plan or program providing the same.

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      6.2 DEFINITION OF DISABILITY

      For purposes hereof, the term "Disability" shall mean an incapacity by
accident, illness or other circumstance which renders the Executive mentally or
physically incapable of performing the duties and services required of the
Executive hereunder on a full-time basis for a period of at least 180
consecutive days.

      6.3 DEFINITION OF "FOR CAUSE" AND "GOOD REASON"

            a. For purposes of Section 6.1, the phrase "for cause" means: (i)
      the Executive's continued and material failure to perform his obligations
      under this Agreement; (ii) the Executive's material failure to adhere to
      any Employer policy or code of conduct; (iii) the appropriation (or
      attempted appropriation) of a material business opportunity of the
      Employer, including attempting to secure or securing any personal profit
      in connection with any transaction entered into on behalf of the Employer;
      (iv) the Executive's engaging in conduct that is materially injurious to
      the Employer, (v) the misappropriation (or attempted misappropriation) of
      any of the Employer's funds or property; (vi) the conviction of or the
      entering of a guilty plea or plea of no contest with respect to, a felony,
      the equivalent thereof, or any other crime with respect to which
      imprisonment is a punishment or; (vii) the conviction of the Executive by
      a court of competent jurisdiction of a crime involving moral turpitude.
      The determination of whether the Executive's employment is terminated for
      cause shall be made solely by the Employer, which shall act in good faith
      in making such determination.

            b. "Good Reason" means:

                  i. The occurrence, prior to a Change of Control or after the
            date which is 12 months after a Change of Control occurs, of any one
            or more of the following events without the Executive's express
            written consent: (i) a significant change in the Executive's titles
            or offices from those previously applicable to the Executive (but
            not an alteration in Executive's reporting responsibilities); (ii) a
            reduction in the Executive's Salary from that provided to him
            immediately on the Effective Date of this Agreement (or the
            effective date of any extension of this Agreement pursuant to
            Section 2.2 or as the same may be increased from time to time; or
            (iii) a diminution in employee benefits (including but not limited
            to medical, dental, life insurance and long-term disability plans)
            and perquisites applicable to the Executive from those substantially
            similar to the employee benefits and perquisites provided by the
            Employer (including subsidiaries) to executives with comparable
            duties; or

                  ii. The occurrence, within 12 months after the date upon which
            a Change of Control occurs, of any one or more of the following
            events without Executive's express written consent: (i) a change in
            Executive's reporting responsibilities, titles or offices as in
            effect immediately prior to the Change of Control or any removal of
            Executive from, or any failure to re-elect Executive to, any of such
            positions which has the effect of diminishing Executive's
            responsibility or authority; (ii) a

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            reduction by the Employer or a subsidiary thereof in Executive's
            Salary as in effect immediately prior to the Change of Control or as
            the same may be increased from time to time or a change in the
            eligibility requirements or performance criteria under any bonus,
            incentive or compensation plan, program or arrangement under which
            Executive is covered immediately prior to the Change of Control
            which adversely affects Executive; (iii) the Employer or a
            subsidiary thereof requiring Executive to be permanently based
            anywhere other than within 50 miles of Executive's job location at
            the time of the Change of Control; (iv) without replacement by a
            plan providing benefits to Executive equal to or greater than those
            discontinued, the failure by the Employer or a subsidiary thereof to
            continue in effect, within its maximum stated term, any pension,
            bonus, incentive, stock ownership, purchase, option, life insurance,
            health, accident, disability, or any other employee benefit plan,
            program or arrangement in which Executive is participating at the
            time of the Change of Control, or the taking of any action by the
            Employer or a subsidiary thereof that would adversely affect
            Executive's participation or materially reduce Executive's benefits
            under any of such plans; (v) the taking of any action by the
            Employer or a subsidiary thereof that would materially adversely
            affect the physical conditions existing at the time of the Change of
            Control in or under which Executive performs his employment duties;
            (vi) if Executive's primary employment duties are with a subsidiary
            of the Employer, the sale, merger, contribution, transfer or any
            other transaction in conjunction with which the Employer's ownership
            interest in the subsidiary decreases below a majority interest; or
            (vii) any material variance from the terms of this Agreement by the
            Employer or a subsidiary thereof.

      6.4 SEVERANCE

      Should the Executive's employment with the Employer be terminated during
the Employment Period pursuant to Section 6.1(e) or Section 6.1(f) above, the
Executive shall be entitled to:

            a. a payment equal to two years of his then current Salary; and

            b. a payment equal to two times his then current cash bonus target
      amount.

      Such payments under this section will be made no later than 30 days
following the termination from employment. Severance payments do not constitute
continued employment beyond the termination date.

      6.5 CHANGE OF CONTROL

      If, within 12 months of a Change of Control, the Executive's position is
eliminated or the Executive is terminated pursuant to Section 6.1(e) or 6.1(f)
above, regardless of whether such termination event occurs during or after the
Employment Period, the Executive shall be entitled to the following in lieu of
the amounts set forth in Section 6.4:

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            a. a payment equal to two years of his then current Salary;

            b. a payment equal to two times his then current cash bonus target
      amount;

            c. potential vesting of Executive's Stock Option award pursuant to
      Section 3.1(c) above, subject to the terms and conditions of the Executive
      Stock Option Agreement and

            d. continued medical and life insurance benefits at no cost to the
      Executive, for the Executive and his dependents (including his spouse) who
      were covered as of such termination event under the medical and life
      insurance benefit plan as in effect for employees of the Employer during
      the coverage period, or the substantial equivalence, for 18 months or
      until such time that he is re-employed and is provided medical and life
      insurance benefits (which coverage shall be promptly reported to the
      Employer by the Executive) whichever is sooner.

      Severance payments do not constitute continued employment beyond the
termination date.

      Notwithstanding anything to the contrary in this Agreement, if the
Executive is a "disqualified individual" (as defined in Section 280G(c) of the
Internal Revenue Code of 1986, as amended (the "Code")), and the severance
benefits provided for in this Section 6.5, together with any other payments and
benefits which the Executive has the right to receive from the Employer and its
affiliates, would constitute a "parachute payment" (as defined in Section
280G(b)(2) of the Code), then the severance benefits provided hereunder
(beginning with any benefit to be paid in cash hereunder) shall be either (1)
reduced (but not below zero) so that the present value of such total amounts and
benefits received by the Executive will be one dollar ($1.00) less than three
times the Executive's "base amount" (as defined in Section 280G of the Code) and
so that no portion of such amounts and benefits received by the Executive shall
be subject to the excise tax imposed by Section 4999 of the Code or (2) paid in
full, whichever produces the better net after-tax position to the Executive
(taking into account any applicable excise tax under Section 4999 of the Code
and any other applicable taxes). The determination as to whether any such
reduction in the amount of the severance benefit is necessary shall be made
initially by the Employer in good faith. If a reduced severance benefit is paid
hereunder in accordance with clause (1) of the first sentence of this paragraph
and through error or otherwise that payment, when aggregated with other payments
and benefits from the Employer (or its affiliates) used in determining if a
"parachute payment" exists, exceeds one dollar ($1.00) less than three times the
Executive's base amount, then the Executive shall immediately repay such excess
to the Employer upon notification that an overpayment has been made.

      6.6 NO MITIGATION

      Any remuneration received by the Executive from a third party following
the Employment Period shall not apply to reduce the Employer's obligations to
make payments hereunder.

      6.7 LIQUIDATED DAMAGES

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      Due to the difficulties in estimating damages for an early termination of
the Employment Period, the Employer and the Executive agree that the payments,
if any, to be received by the Executive hereunder shall be received as
liquidated damages.

7.    NON-DISCLOSURE COVENANT; EMPLOYEE INVENTIONS

      7.1 ACKNOWLEDGMENTS BY THE EXECUTIVE

      The Executive acknowledges that (a) prior to and during the Employment
Period and as a part of his employment, the Executive has been and will be
afforded access to Confidential Information; (b) public disclosure of such
Confidential Information could have an adverse effect on the Employer and its
business; (c) because the Executive possesses substantial technical expertise
and skill with respect to the Employer's business, the Employer desires to
obtain exclusive ownership of each Employee Invention, and the Employer will be
at a substantial competitive disadvantage if it fails to acquire exclusive
ownership of each Employee Invention; and (d) the provisions of this Section 7
are reasonable and necessary to prevent the improper use or disclosure of
Confidential Information and to provide the Employer with exclusive ownership of
all Employee Inventions.

      7.2 AGREEMENTS OF THE EXECUTIVE

      In consideration of the compensation and benefits to be paid or provided
to the Executive by the Employer under this Agreement, the Executive covenants
the following:

            a. Confidentiality.

                  i. The Executive will hold in confidence the Confidential
            Information and will not disclose it to any person except with the
            specific prior written consent of the Employer or except as
            otherwise expressly permitted by the terms of this Agreement.

                  ii. Any trade secrets of the Employer will be entitled to all
            of the protections and benefits under any applicable law. If any
            information that the Employer deems to be a trade secret is found by
            a court of competent jurisdiction not to be a trade secret for
            purposes of this Agreement, such information will, nevertheless, be
            considered Confidential Information for purposes of this Agreement.
            The Executive hereby waives any requirement that the Employer submit
            proof of the economic value of any trade secret or post a bond or
            other security.

                  iii. None of the foregoing obligations and restrictions
            applies to any part of the Confidential Information that the
            Executive demonstrates was or became generally available to the
            public other than as a result of a disclosure by the Executive.

                  iv. The Executive will not remove from the Employer's premises
            (except to

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            the extent such removal is for purposes of the performance of the
            Executive's duties at home or while traveling, or except as
            otherwise specifically authorized by the Employer) any document,
            record, notebook, plan, model, component, device, or computer
            software or code, whether embodied in a disk or in any other form
            (collectively, the "Proprietary Items"). The Executive recognizes
            that, as between the Employer and the Executive, all of the
            Proprietary Items, whether or not developed by the Executive, are
            the exclusive property of the Employer. Upon termination of this
            Agreement by either party, or upon the request of the Employer
            during the Employment Period, the Executive will return to the
            Employer all of the Proprietary Items in the Executive's possession
            or subject to the Executive's control, and the Executive shall not
            retain any copies, abstracts, sketches, or other physical embodiment
            of any of the Proprietary Items.

            b. Employee Inventions. Each Employee Invention will belong
      exclusively to the Employer. The Executive acknowledges that all of the
      Executive's writing, works of authorship, and other Employee Inventions
      are works made for hire and the property of the Employer, including any
      copyrights, patents, or other intellectual property rights pertaining
      thereto. If it is determined that any such works are not works made for
      hire, the Executive hereby assigns to the Employer all of the Executive's
      right, title, and interest, including all rights of copyright, patent, and
      other intellectual property rights, to or in such Employee Inventions. The
      Executive covenants that he will promptly:

                  i. disclose to the Employer in writing any Employee Invention;

                  ii. assign to the Employer or to a party designated by the
            Employer, at the Employer's request and without additional
            compensation, all of the Executive's right to the Employee Invention
            for the United States and all foreign jurisdictions;

                  iii. execute and deliver to the Employer such applications,
            assignments, and other documents as the Employer may request in
            order to apply for and obtain patents or other registrations with
            respect to any Employee Invention in the United States and any
            foreign jurisdictions;

                  iv. sign all other papers necessary to carry out the above
            obligations; and

                  v. give testimony and render any other assistance in support
            of the Employer's rights to any Employee Invention.

            c. Notice of Intent to Resign. Executive agrees to provide Employer
      with 90 days advance notice of his intention to resign ("Notice Period").
      During the Notice Period, Executive shall continue in the diligent
      fulfillment of all duties of his position and this Agreement. Should
      Executive fail to provide Employer with the full Notice Period, Executive
      shall forfeit that portion of his earned pro-rata yearly cash bonus as
      follows:

      (90 - number of full days of advance notice) / 90) X(times) pro-rata
      earned yearly cash bonus

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      = amount forfeited by Executive.

      Pro-rata earned yearly cash bonus is: (unconditional portion of yearly
      cash bonus, if any, targeted for Executive in the current Fiscal Year) /
      (number of full months worked in the current Fiscal Year / 12).

            d. NonDisparagement. Executive shall not disparage the Employer or
      any of its directors, officers, employees, or agents.

            e. Creative Works. Executive shall not create, assist with or
      consult on any creative works which discuss, describe or reference
      Employer or any executive of Employer. Creative works includes but is not
      limited to novels, nonfiction writings, any authored work, plays,
      screenplays, musicals or the like.

      7.3 DISPUTES OR CONTROVERSIES

      The Executive recognizes that should a dispute or controversy arising from
or relating to this Agreement be submitted for adjudication to any court,
arbitration panel, or other third party, the preservation of the secrecy of
Confidential Information may be jeopardized. All pleadings, documents,
testimony, and records relating to any such adjudication will be maintained in
secrecy and will be available for inspection by the Employer, the Executive, and
their respective attorneys and experts, who will agree, in advance and in
writing, to receive and maintain all such information in secrecy, except as may
be limited by them in writing.

8.    NON-COMPETITION AND NON-INTERFERENCE

      8.1 ACKNOWLEDGMENTS BY THE EXECUTIVE

      The Executive acknowledges that: (a) the services to be performed by him
under this Agreement are of a special, unique, unusual, extraordinary, and
intellectual character; (b) the Employer's business is international in scope
and its products are marketed throughout the United States and the world; (c)
the Employer competes with other businesses that are or could be located in any
part of the United States or the world; (d) the provisions of this Section 8 are
reasonable and necessary to protect the Employer's business; and (e) in
connection with the fulfillment of his duties hereunder and as an employee of
the Employer, the Employer will provide Executive with Confidential Information
necessitating the execution of the covenants contained in this Section 8.

      8.2 COVENANTS OF THE EXECUTIVE

      In consideration of the acknowledgments by the Executive, and in
consideration of the compensation and benefits to be paid or provided to the
Executive by the Employer, the Executive covenants that during and for two (2)
years following the Employment Period he will not, directly or indirectly:

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            a. except in the course of his employment hereunder, engage or
      invest in, own, manage, operate, finance, control, or participate in the
      ownership, management, operation, financing, or control of, be employed
      by, associated with, or in any manner connected with, lend the Executive's
      name or any similar name to, lend Executive's credit to or render services
      or advice to, any business whose products or activities compete in whole
      or in part with the products or activities of the Employer anywhere in the
      world, provided, however, that the Executive may purchase or otherwise
      acquire up to (but not more than) five percent (5%) of any class of
      securities of any enterprise (but without otherwise participating in the
      activities of such enterprise) if such securities are listed on any
      national or regional securities exchange or have been registered under
      Section 12(g) of the Securities Exchange Act of 1934, as amended;

            b. whether for the Executive's own account or for the account of any
      other person, solicit business of the same or similar type being carried
      on by the Employer, from any person known by the Executive to be a
      customer or a potential customer of the Employer, whether or not the
      Executive had personal contact with such person during and by reason of
      the Executive's employment with the Employer; or

            c. whether for the Executive's own account or the account of any
      other person, (i) solicit, employ, or otherwise engage as an employee,
      independent contractor, or otherwise, any person who is an employee (or
      was an employee within two (2) years of the date in question) of the
      Employer at any time during the Employment Period or in any manner induce
      or attempt to induce any employee of the Employer to terminate his
      employment with the Employer; or (ii) interfere with the Employer's
      relationship with any person, including any person who at any time during
      the Employment Period was an employee, contractor, supplier, or customer
      of the Employer.

      If any covenant in this Section 8.2 is held to be unreasonable, arbitrary,
or against public policy, such covenant will be considered to be divisible with
respect to scope, time, and geographic area, and such lesser scope, time, or
geographic area, or all of them, as a court of competent jurisdiction may
determine to be reasonable, not arbitrary, and not against public policy, will
be effective, binding, and enforceable against the Executive.

      The period of time applicable to any covenant in this Section 8.2 will be
extended by the duration of any violation by the Executive of such covenant.

9.    GENERAL PROVISIONS

      9.1 INJUNCTIVE RELIEF AND ADDITIONAL REMEDY

      The Executive acknowledges that the injury that would be suffered by the
Employer as a result of a breach of the provisions of this Agreement (including
any provision of Sections 7 and 8) would be irreparable and that an award of
monetary damages to the Employer for such a breach would be an inadequate
remedy. Consequently, the Employer will have the right, in addition to any

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other rights it may have, to obtain injunctive relief to restrain any breach or
threatened breach or otherwise to specifically enforce any provision of this
Agreement, and the Employer will not be obligated to post bond or other security
in seeking such relief.

      9.2 COVENANTS OF SECTIONS 7 AND 8 ARE ESSENTIAL AND INDEPENDENT COVENANTS

      The covenants by the Executive in Sections 7 and 8 are essential elements
of this Agreement, and without the Executive's agreement to comply with such
covenants, the Employer would not have entered into this Agreement or employed
the Executive. The Employer and the Executive have independently consulted with
their respective counsel and have been advised in all respects concerning the
reasonableness and propriety of such covenants, with specific regard to the
nature of the business conducted by the Employer.

      If the Executive's employment hereunder expires or is terminated, this
Agreement will continue in full force and effect as is necessary or appropriate
to enforce the covenants and agreements of the Executive in Sections 7 and 8.

      9.3 REPRESENTATIONS AND WARRANTIES BY THE EXECUTIVE

      The Executive represents and warrants to the Employer that the execution
and delivery by the Executive of this Agreement do not, and the performance by
the Executive of the Executive's obligations hereunder will not, with or without
the giving of notice or the passage of time, or both: (a) violate any judgment,
writ, injunction, or order of any court, arbitrator, or governmental agency
applicable to the Executive; or (b) conflict with, result in the breach of any
provisions of or the termination of, or constitute a default under, any
agreement to which the Executive is a party or by which the Executive is or may
be bound. The Executive further specifically represents and warrants that he is
not subject to, nor will he violate, any agreement not to compete upon the
execution and delivery by him of this Agreement.

      The Executive represents and warrants that he will not utilize or divulge
any proprietary materials or information from his previous employers and
acknowledges that Employer has prohibited Executive from bringing any such
materials on to Employer's premises and has advised Executive that Executive's
failure to adhere to these prohibitions will subject Executive to immediate
termination.

      9.4 OBLIGATIONS CONTINGENT ON PERFORMANCE

      The obligations of the Employer hereunder, including its obligation to pay
the compensation provided for herein, are contingent upon the Executive's
performance of the Executive's obligations hereunder.

      9.5 WAIVER

      The rights and remedies of the parties to this Agreement are cumulative
and not alternative.

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Neither the failure nor any delay by either party in exercising any right,
power, or privilege under this Agreement will operate as a waiver of such right,
power, or privilege, and no single or partial exercise of any such right, power,
or privilege will preclude any other or further exercise of such right, power,
or privilege or the exercise of any other right, power, or privilege. To the
maximum extent permitted by applicable law, (a) no claim or right arising out of
this Agreement can be discharged by one party, in whole or in part, by a waiver
or renunciation of the claim or right unless in writing signed by the other
party; (b) no waiver that may be given by a party will be applicable except in
the specific instance for which it is given; and (c) no notice to or demand on
one party will be deemed to be a waiver of any obligation of such party or of
the right of the party giving such notice or demand to take further action
without notice or demand as provided in this Agreement.

      9.6 BINDING EFFECT; DELEGATION OF DUTIES PROHIBITED

      This Agreement shall inure to the benefit of, and shall be binding upon,
the parties hereto and their respective successors, assigns, heirs, and legal
representatives, including any entity with which the Employer may merge or
consolidate or to which all or substantially all of its assets may be
transferred. The duties and covenants of the Executive under this Agreement,
being personal, may not be delegated or assigned.

      9.7 NOTICES

      All notices, consents, waivers, and other communications under this
Agreement must be in writing and will be deemed to have been duly given when (a)
delivered by hand (with written confirmation of receipt), (b) sent by facsimile
(with written confirmation of receipt), provided that a copy is mailed by
registered mail, return receipt requested and signed for by the party required
to receive notice, or (c) when received by the addressee, if sent by a
nationally recognized overnight delivery service (receipt requested), in each
case to the appropriate addresses and facsimile numbers set forth below (or to
such other addresses and facsimile numbers as a party may designate by notice to
the other parties):

      If to Employer:

      BMC Software, Inc.
      2101 CityWest Blvd.
      Houston, Texas 77042
      Telephone No.: (713) 918-8800
      Facsimile No.: (713) 918-1110
      Attn:  General Counsel

      If to the Executive, to the last address and phone number provided by
      Executive

      9.8 ENTIRE AGREEMENT; AMENDMENTS

      Except as provided in (a) plans and programs of the Employer referred to
in Sections 3.1(b) through (d), and (b) any signed written agreement
contemporaneously or hereafter executed by the

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Employer and the Executive, this Agreement contains the entire agreement between
the parties with respect to the subject matter hereof and supersedes all prior
agreements and understandings, oral or written, between the parties hereto with
respect to the subject matter hereof. Notwithstanding the foregoing, this
Agreement shall not be construed to supersede any stock option agreements or
restricted stock agreements entered into between Executive and Employer at any
time prior to the execution of this Agreement. This Agreement may not be amended
orally, but only by an agreement in writing signed by the parties hereto.

      9.9 GOVERNING LAW

      THIS AGREEMENT WILL BE GOVERNED BY THE LAWS OF THE STATE OF TEXAS WITHOUT
REGARD TO CONFLICTS OF LAWS PRINCIPLES.

      9.10 ARBITRATION

      In the event that there shall be any dispute arising out of or in any way
relating to this Agreement, the contemplated transactions, any document referred
to or incorporated herein by reference or centrally related to the subject
matter hereof, or the subject matter of any of the same, the parties covenant
and agree as follows:

            a. The parties shall first use their reasonable best efforts to
      resolve such dispute among themselves, with or without mediation.

            b. If the parties are unable to resolve such dispute among
      themselves, such dispute shall be submitted to binding arbitration in
      Houston, Texas, under the auspices of, and pursuant to the rules of, the
      American Arbitration Association's Commercial Arbitration Rules as then in
      effect, or such other procedures as the parties may agree to at the time,
      before a tribunal of three (3) arbitrators, one of which shall be selected
      by the Executive, one of which shall be selected by the Employer, and the
      third of which shall be selected by the two (2) arbitrators so selected.
      Any award issued as a result of such arbitration shall be final and
      binding between the parties, and shall be enforceable by any court having
      jurisdiction over the party against whom enforcement is sought. A ruling
      by the arbitrators shall be non-appealable. The parties agree to abide by
      and perform any award rendered by the arbitrators. If either the Executive
      or Employer seeks enforcement of the terms of this Agreement or seeks
      enforcement of any award rendered by the arbitrators, then the prevailing
      party (designated by the arbitrators) to such proceeding(s) shall be
      entitled to recover its costs and expenses (including applicable travel
      expenses) from the non-prevailing party, in addition to any other relief
      to which it may be entitled. If a dispute arises and one party fails or
      refuses to designate an arbitrator within thirty (30) days after receipt
      of a written notice that an arbitration proceeding is to be held, then the
      dispute shall be resolved solely by the arbitrator designated by the other
      party and such arbitration award shall be as binding as if three (3)
      arbitrators had participated in the arbitration proceeding. Either the
      Executive or the Employer may cause an arbitration proceeding to commence
      by giving the other party notice in writing of such arbitration. Executive
      and the Employer covenant and agree to act as expeditiously as practicable
      in order to resolve all disputes by arbitration. Notwithstanding

                                       21

<PAGE>

      anything in this section to the contrary, neither Executive nor the
      Employer shall be precluded from seeking court action in the event the
      action sought is either injunctive action, a restraining order or other
      equitable relief. The arbitration proceeding shall be held in English.

            c. Legal process in any action or proceeding referred to in the
      preceding section may be served on any party anywhere in the world.

            d. Except as expressly provided herein and except for injunctions
      and other equitable remedies that are required in order to enforce this
      Agreement, no action may be brought in any court of law and EACH OF THE
      PARTIES WAIVES ANY RIGHTS THAT IT MAY HAVE TO BRING A CAUSE OF ACTION IN
      ANY COURT OR IN ANY PROCEEDING INVOLVING A JURY TO THE MAXIMUM EXTENT
      PERMITTED BY LAW. Each party acknowledges that it has been represented by
      legal counsel of its own choosing and has been advised of the intent,
      scope and effect of this Section 9.10 and has voluntarily entered into
      this Agreement and this Section 9.10.

            e. Excluded from this Section 9.10 are any claims for temporary
      injunctive relief to enforce Sections 7 and 8 of this Agreement.

      9.11 SECTION HEADINGS, CONSTRUCTION

      The headings of Sections in this Agreement are provided for convenience
only and will not affect its construction or interpretation. All references to
"Section" or "Sections" refer to the corresponding Section or Sections of this
Agreement unless otherwise specified. All words used in this Agreement will be
construed to be of such gender or number as the circumstances require. Unless
otherwise expressly provided, the word "including" does not limit the preceding
words or terms.

      9.12 SEVERABILITY

      If any provision of this Agreement is held invalid or unenforceable by any
court of competent jurisdiction, the other provisions of this Agreement will
remain in full force and effect. Any provision of this Agreement held invalid or
unenforceable only in part or degree will remain in full force and effect to the
extent not held invalid or unenforceable.

      9.13 COUNTERPARTS

      This Agreement may be executed in one or more counterparts, each of which
will be deemed to be an original copy of this Agreement and all of which, when
taken together, will be deemed to constitute one and the same agreement.

      9.14 WAIVER OF JURY TRIAL

      THE PARTIES HERETO HEREBY WAIVE A JURY TRIAL IN ANY LITIGATION

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<PAGE>

WITH RESPECT TO THIS AGREEMENT.

      9.15 WITHHOLDING OF TAXES AND OTHER EMPLOYEE DEDUCTIONS

The Employer may withhold from any payments and benefits made pursuant to this
Agreement all federal, state, city, and other taxes as may be required pursuant
to any law or governmental regulation or ruling and all other normal deductions
made with respect to the Employer's employees generally.

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<PAGE>

      IN WITNESS WHEREOF, the parties have executed and delivered this Agreement
as of the date above first written above.

                                    EMPLOYER:

                                    BMC Software, Inc.

                                    By: /s/ Jerome Adams
                                    Name: Jerome Adams
                                    Title: SVP Administration

                                    EXECUTIVE:

                                    By: /s/ Cosmo Santullo
                                    Name: Cosmo Santullo

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<PAGE>

                                                                   Attachment A

                               BMC SOFTWARE, INC.
                         EXECUTIVE EMPLOYMENT AGREEMENT
                             CASH BONUS DESCRIPTION

      The Executive will, during the Employment Period, be permitted to
participate in the BMC Annual Executive Incentive Plan that may be in effect
from time to time. During the employment period, the Executive will be eligible
to receive a target incentive, which is 150% of base salary. The actual amount
received is not guaranteed and is dependent on the performance of the Company
and the Executive in accordance with the Annual Incentive Plan established for
each fiscal year during the employment period.

      Each fiscal year, the Executive will receive a detailed description of the
Annual Incentive Plan and the targeted measures and objectives for that year.

                                       25