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                                                                    Exhibit 10.1


                       MANTECH INTERNATIONAL CORPORATION

                         EMPLOYEE STOCK OWNERSHIP PLAN

                         (as effective January 1, 1999)

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                               TABLE OF CONTENTS

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PREAMBLE............................................................    iv

SECTION 1   DEFINITIONS

    1.1   Account...................................................     1
    1.2   Affiliate.................................................     1
    1.3   Appropriate Form..........................................     1
    1.4   Beneficiary...............................................     1
    1.5   Board of Directors........................................     1
    1.6   Break in Service..........................................     1
    1.7   Code......................................................     2
    1.8   Committee.................................................     2
    1.9   Company...................................................     2
   1.10   Company Stock.............................................     2
   1.11   Compensation..............................................     2
   1.12   Disability................................................     2
   1.13   Effective Date............................................     2
   1.14   Eligible Employee.........................................     2
   1.15   Employee..................................................     3
   1.16   Employer..................................................     3
   1.17   Employer Contribution.....................................     3
   1.18   Entry Date................................................     3
   1.19   ERISA.....................................................     3
   1.20   Hour of Service...........................................     3
   1.21   Limitation Year...........................................     4
   1.22   Normal Retirement Age.....................................     4
   1.23   Participant...............................................     4
   1.24   Plan......................................................     4
   1.25   Plan Year.................................................     4
   1.26   Transfer Agent............................................     4
   1.27   Trust Agreement...........................................     4
   1.28   Trust Fund................................................     4
   1.29   Trustee...................................................     4
   1.30   Valuation Date............................................     4
   1.31   Year of Service...........................................     4

SECTION 2   PARTICIPATION

    2.1   Eligibility for Participation.............................     5
    2.2   Designation of Beneficiary................................     5
    2.3   Continuation of Participation.............................     5
    2.4   Transfers to or from Employment with an Affiliate.........     6
    2.5   Transfers to or from Non-Covered Status...................     6
    2.6   Reemployment..............................................     6
    2.7   Service with the Armed Forces.............................     6
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SECTION 3   CONTRIBUTIONS

    3.1   Employer Contributions.......................................    8
    3.2   Payment of Employer Contributions............................    8
    3.3   No Participant or Rollover Contributions.....................    8
    3.4   Maximum "Annual Additions"...................................    8
    3.5   Refund of Contributions......................................    9

SECTION 4   PARTICIPANT ACCOUNTS

    4.1   Establishment of Participant Accounts........................   10
    4.2   Valuation of Accounts........................................   10
    4.3   Share Accounting/Dividends...................................   10
    4.4   Investing Contracts..........................................   10
    4.5   Transactions to Which Code Section 1042 Applies..............   11

SECTION 5   VESTING

    5.1   Vesting of Participant's Accounts............................   12
    5.2   Special Vesting Provisions...................................   12
    5.3   Application of Forfeitures...................................   12
    5.4   Reemployment, Repayment and Restoration of Forfeiture........   13

SECTION 6   INVESTMENT OF ACCOUNTS

    6.1   Investment of Accounts.......................................   14
    6.2   Diversification of Investments...............................   14

SECTION 7   DISTRIBUTIONS UPON TERMINATION OF SERVICE

    7.1   Distributions upon Retirement, Death of Disability...........   16
    7.2   Distributions upon Other Termination of Service..............   16

SECTION 8   PROVISIONS CONCERNING PAYMENT OF BENEFITS

    8.1   Payment of Benefits..........................................   17
    8.2   Identity of Payee............................................   18
    8.3   Latest Commencement of Benefits..............................   18
    8.4   Required Minimum Distributions...............................   19
    8.5   Direst Rollover From the Plan................................   19
    8.6   Non-Alienation of Benefits...................................   21

SECTION 9   ADMINISTRATION OF THE PLAN

    9.1   Named Fiduciary and Plan Administrator.......................   22
    9.2   Committee....................................................   22
    9.3   Rules and Regulations........................................   23
    9.4   Voting Company Stock.........................................   24
    9.5   Claims for Benefits..........................................   25
    9.6   Records and Reports..........................................   26
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                                       ii

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    9.7   Required Information.........................................   26
    9.8   Payment of Expenses..........................................   26
    9.9   Indemnification..............................................   27

SECTION 10  MANAGEMENT OF THE TRUST FUND

   10.1   Trustee......................................................   28
   10.2   Trust Fund..................................................    28

SECTION 11  AMENDMENT, MERGER AND TERMINATION OF THE PLAN

   11.1   Amendment....................................................   29
   11.2   Merger, Consolidation or Sale of the Employer................   29
   11.3   Suspension or Termination....................................   30
   11.4   Vesting and Maintenance of Accounts..........................   30

SECTION 12  ADOPTION OF PLAN BY AFFILIATE

   12.1   Adoption.....................................................   31
   12.2   Modification of adoption.....................................   31

SECTION 13  IN EVENT PLAN BECOMES TOP-HEAVY

   13.1   Purpose and Limited Application of this Section..............   32
   13.2   Special Definitions..........................................   32
   13.3   Special Top-Heavy Rules......................................   33

SECTION 14  MISCELLANEOUS PROVISIONS

   14.1   Limitation of Liability......................................   35
   14.2   Identity of Payee............................................   35
   14.3   Applicability................................................   35
   14.4   Limitation of Rights.........................................   35
   14.5   Plan not a Condition of Employment...........................   35
   14.6   Assumption of Risk by Participants...........................   36
   14.7   Uniform Administration.......................................   36
   14.8   Severability.................................................   36
   14.9   Titles and Headings..........................................   36

SECTION 15  EXECUTION..................................................   37
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                                      iii

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                                    PREAMBLE

The purpose of this Plan is to enable participating employees of the Company to
acquire a proprietary interest in the Company, to share in the growth and
prosperity of the Company, and to accumulate capital for their future economic
security. Because the primary purpose is to enable participants to share in the
growth of the Company, contributions will be invested primarily in stock of the
Company.

The Plan is designed to do this without requiring any withholding from
participants' paychecks and without calling upon participants to invest their
personal savings. This Plan is intended to qualify as an employee stock
ownership plan of the stock bonus variety under Section 401(a) and Section
4975(e)(7) of the Internal Revenue Code. All assets acquired under this Plan as
a result of Company contributions, income and other additions to the Trust will
be administered, distributed, forfeited and otherwise governed by the provisions
of this Plan, which will be administered by the Company for the exclusive
benefit of participants and their beneficiaries.

This Plan is effective as of January 1, 1999.

                                       iv

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                                   SECTION 1
                                  Definitions

     As used herein, the following terms will have the following respective
meanings, unless a different meaning is required by the context. Some of the
words and phrases used in the Plan are not defined in this Section 1, but for
convenience are defined as they are introduced into the text. The masculine
pronoun, wherever used herein will include the feminine pronoun, and the
singular will include the plural.

1.1     "Account" means the separate account maintained for a Participant to
record his or her share of the Trust Fund attributable to Employer Contributions
and earnings thereon.

1.2     "Affiliate" means any company substantially all the assets of which have
been or are acquired by the Company, or any company which is related to the
Company as a member of a controlled group of corporations in accordance with
Section 414(b) of the Code or as a trade or business under common control, as
defined in Section 414(c) of the Code, any organization which is part of an
affiliated service group, as defined in Section 414(m) of the Code, or any
entity required to be aggregated with the Company, as defined in Section 414(o)
of the Code and the regulations thereunder. For purposes under the Plan of
determining whether or not a person is an Employee and the period of employment
of such person, each such other company shall be included as an "Affiliate" only
for such period or periods during which such other company is a member of the
controlled group, under common control, an affiliated service group or otherwise
required to be so aggregated, unless the Board of Directors shall determine, as
to any other company, that such company, shall be deemed an "Affiliate" for an
extended prior period. An Affiliate is not necessarily an Employer for purposes
of the Plan. See Sections 1.16 and 12.1 of the Plan.

1.3     "Appropriate Form" means the form prescribed by the Committee for the
particular purpose provided in the applicable section of the Plan, or if no form
is prescribed, in a form acceptable to the Committee.

1.4     "Beneficiary" means the person or persons so designated by a Participant
to receive benefits payable under the Plan as a result of the death of the
Participant, as provided in Section 2.2.

1.5     "Board of Directors" means the Board of Directors of the Company.

1.6     "Break in Service" means any Plan Year during which an Employee is
credited with less than 501 Hours of Service. Solely for purposes of determining
if a Break in Service has occurred, Hours of Service shall be recognized for (a)
any leaves of absence granted to an Employee on a uniform basis in accordance
with established practices of the Company including military leaves of absence
and (b) any absences from work by reason of the Employee's pregnancy, birth of
the Employee's child, placement of a child with the Employee in connection with
the adoption of such child, or any absence for the purpose of caring for such
child immediately following such birth or

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placement. However, the maximum number of Hours of Service granted to an
Employee on a leave of absence under (b) in the preceding sentence shall be an
amount that would prevent the Employee from incurring a Break in Service in the
Plan Year during which the leave occurs or in the immediately following Plan
Year.

1.7    "Code" means the Internal Revenue Code of 1986, as amended from time to
time.

1.8    "Committee" means the ESOP Administration Committee appointed by the
Board of Directors to manage and administer the Plan in accordance with the
provisions of Section 9.

1.9    "Company" means ManTech International Corporation.

1.10   "Company Stock" means the authorized Class A common stock issued by
ManTech International Corporation.

1.11   "Compensation" means the Employee's base wage or salary (paid in cash or
its equivalent), overtime pay, salary reductions under Code Section 401(k) and
Code Section 125, but excluding bonuses, PIPs (performance incentive plan
payments) commissions, reimbursements and other expense allowances, fringe
benefits (cash or noncash), employee welfare benefits, and moving expenses for
the Plan Year. Base wages or salary shall include amounts which continue to be
paid directly by the Company during temporary absences from work including but
not limited to absences due to vacation, holiday, injury, illness, jury duty,
and military duty. Compensation in excess of $150,000, subject to adjustment as
provided in Section 401(a)(17) of the Code, shall be disregarded for all
purposes under the Plan, except as otherwise provided in Section 3.4 of the
Plan. Compensation shall be determined on a Plan Year basis without regard as to
whether an Employee was a Participant for the entire Plan Year.

1.12   "Disability" shall mean any permanent and lasting inability, by reason of
       physical or mental infirmity, or both, of a Participant to engage in any
       substantial gainful activity. The Committee shall determine whether a
       Participant has incurred a Disability on the basis of medical evidence
       satisfactory to the Committee.

1.13   "Effective Date" means January 1, 1999.

1.14   "Eligible Employee" means any employee of the Employer, except (a) any
"leased employee" within the meaning of Section 414(n) of the Code; (b) any
Employee who is a nonresident alien who receives no earned income within the
meaning of Section 911(d)(2) of the Code from the Company which constitutes
income from sources within the United States within the meaning of Section
861(a)(3) of the Code; (c) any person who the Employer, in its sole discretion,
determines not to be an employee of the Employer, with reference to either (i)
the Employer's standard hiring practices or policies or (ii) an agreement
between the Employer and such person that such person is not an employee of the
Employer, even though such person subsequently is considered, or determined to
be, an Eligible Employee of the Employer; or (d)

                                       2

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George J. Pedersen. The Committee shall determine the employee status of each
such person based upon information furnished by the Employer. Such determination
shall be conclusive and binding upon all persons, provided the same is made
pursuant to the Plan.

1.15   "Employee" means any person performing services for the Company or any
Affiliate, including a "leased employee" as defined in Section 414(n) of the
Code.

1.16   "Employer" means the Company and any Affiliate which, with the approval
of the Board of Directors, adopts the Plan as provided in Section 12.1, and any
successor thereto which agrees to continue this Plan.

1.17   "Employer Contribution" means payments made to or Company Stock
contributed to the Trust Fund by the Employer.

1.18   "Entry Date" means each December 30th.

1.19   "ERISA" means Employee Retirement Income Security Act of 1974, as
amended.

1.20   "Hour of Service" means each hour of service for which an Employee is
credited under the Plan, in accordance with the following rules:

       (a) Hours of Service shall include each hour of service for which an
Employee is paid (or entitled to payment) for the performance of duties; each
hour of service for which an Employee is paid (or entitled to payment) for a
period during which no duties are performed (irrespective of whether service has
terminated) due to vacation, holiday, illness, incapacity (including
Disability), layoff, jury duty, military duty or leave of absence; and each
additional hour of service for which back pay is either awarded or agreed to
(irrespective of mitigation of damages); provided, however, that not more than
501 Hours of Service shall be credited for a single continuous period during
which an Employee does not perform any duties (whether or not such period occurs
in a single Plan Year).

       (b) The crediting of Hours of Service shall be determined in accordance
with the rules set forth in paragraphs (b) and (c) of Section 2530.200b-2 of the
regulations prescribed by the Department of Labor, which rules shall be
consistently applied with respect to all Employees within the same job
classification. Each Employee shall be credited with his actual hours.

       (c) Hours of Service shall not be credited to an Employee for a period
during which no duties are performed if payment is made or due under a plan
maintained solely for the purpose of complying with applicable worker's
compensation, unemployment compensation or disability insurance laws, and Hours
of Service shall not be credited on account of any payment made or due an
Employee solely in reimbursement of medical or medically-related expenses.

                                       3

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1.21  "Limitation Year" means the calendar year.

1.22  "Normal Retirement Age" means age 60.

1.23  "Participant" means any person who meets the requirements for
participation as provided in Section 2.

1.24  "Plan" means the ManTech International Corporation Employee Stock
Ownership Plan, as set forth herein, or as it may be amended from time to time.

1.25  "Plan Year" means (a) the period beginning on January 1, 1999 and ending
on December 30, 1999 or (b) for plan years beginning after December 30, 1999,
the twelve-month period commencing on each December 31 and ending on the next
following December 30.

1.26  "Transfer Agent" means the keeper of record of information with respect to
each registered shareholder, including such information as name of, address of
and the number of shares owned by the registered shareholder, and who is
authorized to transfer the certificates of Company Stock. The Transfer Agent
shall be the person selected by the Company for such purpose, and in absence
thereof the Transfer Agent shall be the Company.

1.27  "Trust Agreement" shall mean the agreement(s) entered into between the
Company and the Trustee(s) under the Plan, as provided for in Section 10.

1.28  "Trust Fund" shall mean all funds held, at any time, by the Trustee(s)
under the Trust Agreement(s).

1.29  "Trustee" shall mean the person or persons, institutions, corporations,
associations or a combination thereof, or any successor thereof, who or which,
at any time, may be acting as a Trustee under the Trust Agreement.

1.30  "Valuation Date" shall mean each December 30th and such other dates or
dates deemed necessary by the Committee.

1.31  "Year of Service" means each Plan Year during which an Employee is
credited with at least 1,000 Hours of Service with the Company or any Affiliate.
If an Employee incurs five consecutive one-year Breaks in Service and was not
vested in any part of his or her Account (determined in accordance with Section
5) prior to such Breaks in Service shall be disregarded. For vesting purposes,
Years of Services shall include periods prior to the Effective Date.

                                       4

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                                   SECTION 2
                                 Participation

2.1    Eligibility for Participation

       Each Employee shall become a Participant as of the next Entry Date
       coinciding with or following the date he or she becomes an Eligible
       Employee. Notwithstanding anything herein to the contrary, each Eligible
       Employee employed on or before the Effective Date shall participate in
       the Plan as of the Effective Date, provided such Eligible Employee has
       performed an Hour of Service on or after the Effective Date.

2.2    Designation of Beneficiary

       A Participant may designate a Beneficiary to receive any death benefits
       arising under the Plan by filing an Appropriate Form with the Committee.
       The Beneficiary may be a designated person or persons, trust or trusts,
       provided that, if more than one person or trust is named, the Participant
       must indicate the percentage of the account and/or precedence of each
       person or trust. A Participant may change his or her Beneficiary from
       time to time by filing the Appropriate Form. Notwithstanding the
       foregoing, the Beneficiary with respect to a married Participant shall
       be, in all events, such Participant's surviving spouse, if any, unless
       such spouse consents in writing to the designation of another Beneficiary
       or to any subsequent change in Beneficiary (unless the consent of the
       spouse expressly permits designations by the Participant without any
       requirements for future consent by the spouse). A spouse shall be deemed
       to have given such consent if it is established to the satisfaction of
       the Committee that actual written consent to such election cannot be
       obtained from the spouse because the spouse cannot be located or because
       of such other circumstances as may be prescribed in accordance with
       Treasury Regulation Section 1.401(a)-20, Q&A-27. Any such consent
       (including such deemed consent) by a spouse shall be effective only with
       respect to such spouse. The spousal consent is irrevocable, must
       acknowledge the effect of such election and must be witnessed by a Plan
       representative or a notary public. In the event that no Beneficiary had
       been designated or that no designated Beneficiary survives the
       Participant, the following Beneficiaries (if then living) shall be deemed
       to have been designated in the following priority: (1) spouse, (2)
       children, including adopted children, in equal shares, per stirpes, (3)
       parents, in equal shares, (4) the person(s) designated as beneficiary
       under any group life insurance maintained by the Employer, and (5) the
       Participant's estate.

2.3    Continuation of Participation

       Each Participant shall continue to be a Participant as long as an Account
       is maintained on his or her behalf.

                                       5

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2.4  Transfers to or From Employment with an Affiliate

     The transfer of a Participant from the payroll of one Employer to that of
     another Employer shall not constitute a termination of employment and he or
     she shall continue as a Participant. The transfer of a Participant to the
     payroll of an Affiliate that is not an Employer shall not constitute a
     termination of employment and he or she shall be suspended until such time
     as he or she may again be employed as an Eligible Employee by an Employer
     participating in the Plan. Termination of employment (other than by
     transfer to another Affiliate) with the Affiliate to whose payroll he or
     she has transferred, shall constitute a termination of employment or
     retirement, as applicable, under the plan. If a Participant who has
     transferred to the payroll of an Affiliate that is not an Employer is again
     employed as an Eligible Employee by an Employer participating in the Plan,
     Employer Contributions on his or her behalf shall resume immediately upon
     performing an Hour of Service for the Employer participating in the Plan.

2.5  Transfer to or from Non-Covered Status

     If a participant ceases to meet the definition of Eligible Employee but
     continues in the employment of an Employer, he or she shall be treated as
     if he or she were transferred to the payroll of an Affiliate that is not an
     Employer. In the event that such Participant is again employed as an
     Eligible Employee by an Employer participating in the Plan, Employer
     contributions on his or her behalf shall resume immediately upon performing
     an Hour of Service for the Employer participating in the Plan.

2.6  Reemployment
     If a participant terminates employment and again is employed as an Eligible
     Employee by an Employer participating in the Plan, Employer contributions
     on his or her behalf shall resume immediately upon performing an Hour of
     Service for the Employer participating in the Plan. If an Eligible Employee
     terminates employment prior to becoming a Participant and is again employed
     as an Eligible Employee by an Employer participating in the Plan, he or she
     shall be eligible to become a Participant pursuant to Section 2.1 above.

2.7  Service with the Armed Forces
     A Participant who leaves employment with the Employer to enter the United
     States Armed Forces or the Merchant marine shall not be deemed to have
     terminated employment for the purposes of this Plan and shall be
     conclusively presumed to be on leave of absence, provided such Participant
     is entitled to reemployment rights and returns to work for the Employer,
     without any intervening employment elsewhere, within 90 days after his or
     her discharge from qualified military service, as prescribed by the
     applicable laws of the United States. Notwithstanding any provision of this
     Plan to the contrary,

                                       6

<PAGE>

     contributions, benefits and service credit with respect to qualified
     military service will be provided in accordance with Section 414(u) of the
     Code.

                                       7

<PAGE>

                                   SECTION 3
                                 Contributions

3.1    Employer Contributions

       For each Plan Year, the Company may make an Employer Contribution to the
       Trust Fund in such amount or under such formula, at such times, as may be
       determined by the Board of Directors, in its sole and absolute
       discretion. A Participant is entitled to share in the allocation of the
       Employer Contribution for each Plan Year in which he or she is credited
       with at least 1000 Hours of Service and in which he or she is an Eligible
       Employee on the last day of the Plan Year. The Employer Contribution
       shall be allocated among the Accounts of eligible Participants (as
       described in the preceding sentence) in the proportion that the
       Compensation earned during the Plan Year by each eligible Participant
       bears to the sum of the Compensation earned by all eligible Participants
       during the Plan Year.

3.2    Payment of Employer Contributions

       The Employer Contribution for each Plan Year shall be made to the Trust
       Fund not later than the due date (including extensions) for filing the
       Company's federal income tax return for that Plan Year. The Employer
       Contribution may be made in cash and/or in shares or Company Stock, or
       may be made in one or more installments, as determined by the Board of
       Directors, in its sole and absolute discretion. The Employer Contribution
       made in shares of Company Stock shall be valued based upon their fair
       market value as of the most recent prior Valuation Date. Each Employer
       shall be responsible for its allocable share of the aggregate
       contribution equal to the total amount to be allocated to the Account of
       each Participant who the Employer employs and who is eligible to receive
       an allocation for the applicable Plan Year.

3.3    No Participant or Rollover Contributions

       No Participant shall be required or permitted to make contributions to
       the Trust. No rollover contributions from other qualified plans are
       permitted.

3.4    Maximum "Annual Additions"

       Notwithstanding the foregoing provisions of this Section 3, the total
       "annual additions" (as hereinafter defined) with respect to any
       Participant for any Limitation Year shall not exceed the lesser of:
             (a) 25% of the Participant's "Section 415 compensation" (as
                 determined under Section 415(c)(3) of the Code and in Treasury
                 Regulation Section 1.415-2(d)(1) and (2)) for the Limitation
                 Year, or
             (b) the dollar limit in effect for such Limitation Year in
                 accordance with Section 415(c)(2)(A) of the Code.

                                       8

<PAGE>

         For purposes of this Section 3.4, the term "annual additions" with
         respect to any Participant means the sum of:
              (a) Employer Contributions pursuant to Section 3.1, and
              (b) forfeitures, if any.

         For the purposes of this Section 3.4 and determining whether the amount
         of annual additions (within the meaning of Section 415(c)(2) of the
         Code) are within the limits of Section 415(c) of the Code for any
         Limitation Year, if a Participant also is participating in any other
         tax-qualified defined contribution plan or plans maintained by the
         Employer or an Affiliate, the annual additions under the Plan and the
         amount of annual additions (within the meaning of Section 415(c)(2) of
         the Code) under all such other defined contribution plans shall be
         combined. If any Participant's annual additions would exceed the limits
         of Section 415(c) of the Code for any Limitation Year, such excess
         shall be eliminated by reducing contributions allocable to such
         Participant under any other tax-qualified defined contribution plan
         maintained by the Employer or an Affiliate (pursuant to the terms of
         that plan) to the extent necessary to meet the limitations. If a
         Participant in this Plan is a participant in any qualified defined
         benefit plan maintained by the Employer or Affiliate, the overall
         limitation of Section 415(e) of the Code shall be complied with by
         limiting the amount of pension payable to such person under such
         defined benefit plan without adjustment to the limitation applicable to
         such Participant under this Plan.

3.5      Refund of Contributions

         All Employer Contributions under this Plan are conditioned upon initial
         qualification of the Plan under Section 401 of the Code. If it is
         determined that the Plan does not so qualify, the appropriate
         contributions shall be returned to the Employer within one year after
         the date of such denial of initial qualification. All Employer
         Contributions under the Plan are made on the condition that current tax
         deductions are allowed for such contributions under Section 404 of the
         Code. If, and to the extent, a deduction is not allowed for Employer
         Contributions under the Plan for a taxable year, an amount equal to the
         contributions so disallowed as a deduction for such year shall be
         repaid by the Trustee to the Employer within one year after such
         disallowance, provided the Employer so directs the Trustee and such
         repayment will not adversely affect the qualified status of the Plan.
         Refunds of contributions shall be made to the Employer in the case of a
         contribution which is made by reason of a mistake of fact (for example,
         incorrect information as to eligibility or Compensation of an Employee,
         a mathematical error or an erroneous belief that such contribution is
         consistent with the limitations in Section 3.4). So much of the
         contribution as is attributable to the mistake of fact shall be repaid
         by the Trustee upon demand by the Employer, presentation of evidence of
         the mistake of fact and calculation as to the impact of the mistake,
         provided such demand and repayment is made within one year after the
         payment of contribution to which the mistake applies.

                                       9

<PAGE>

                                    SECTION 4
                              Participant Accounts

 4.1     Establishment of Participant Accounts

         The Committee shall maintain a separate Account for each Participant
         setting forth the balance of the Participant's Account. Each Account
         shall be maintained primarily in terms of Company Stock. The Committee
         shall make the allocation among and adjustments to such Participant
         Accounts as provided in Sections 3.1 and 4.2 of the Plan.

 4.2     Valuation of Accounts

         The value of the Trust Fund, as of any date of determination, shall be
         determined by the Trustee on the basis of fair market value as of the
         preceding Valuation Date. As of each Valuation Date, the value of the
         Trust Fund shall be adjusted by the Trustee so as to reflect the effect
         of income collected or accrued, realized and unrealized profits and
         losses, distributions, withdrawals, contributions, and all other
         transactions since the preceding Valuation Date. The value of each
         Participant's Account, as of any Valuation Date, shall be its share of
         the value of the Trust Fund as of the preceding Valuation Date, as so
         adjusted, which share shall be determined by the Committee with
         reference to the ratio in which the balance of Participant's Account on
         the preceding Valuation Date bears to the sum of the balances for the
         Accounts of all Participants on that date.

 4.3     Share Accounting/Dividends

         To the extent that the Plan holds shares of Company Stock, then
         notwithstanding the other provisions of Section 4, the Committee may
         segregate those shares and account for them separately. In any event,
         dividends paid or accrued on Company Stock shall be allocated to the
         Accounts which hold such Company Stock. However, the Company may direct
         that dividends be paid or distributed to the Participants in accordance
         with Code Section 404(k). Any Company Stock dividend paid on Company
         Stock held by the Trust Fund shall be treated as a Company Stock split.

4.4      Investment Contracts

         Notwithstanding any provision to the contrary, if any Trust Fund assets
         are invested through any arrangement with an insurance company or other
         investment organization, Accounts shall be valued and gains, losses,
         costs, and expenses shall be allocated (but not less frequently than
         annually) in accordance with the terms of the applicable investment
         contract or arrangement.

                                       10

<PAGE>

4.5      Transactions to Which Code Section 1042 Applies

         If the Plan acquires any Company Stock in a transaction to which Code
         Section 1042 applies, then notwithstanding any other provision of this
         Section 4, no Company Stock acquired in such a transaction shall be
         allocated in violation of Code Section 409(n) to the Account of any
         Participant (or of any relative, within the meaning of Code Section
         267(b), of such Participant) who makes an election under Code Section
         1042 or any Participant who is a more-than-25% owner in the Company.

                                       11

<PAGE>

                                    SECTION 5
                                    Vesting

5.1      Vesting of Participant's Account

         A Participant's Account shall vest on the basis of his or her Years of
         Service, in accordance with the following schedule:

                        Years of                                   Vested
                        Service                                  Percentage
                        -------                                  ----------

                      Less than 2 years                              0%
                      2 years but less than 3 years                 25%
                      3 years but less than 4 years                 50%
                      4 years but less than 5 years                 75%
                      5 years or more                              100%

5.2      Special Vesting Provisions

         A Participant's Account shall automatically become 100% vested upon:

         (a) his or her Disability or death prior to the termination of his or
             her employment;

         (b) his or her attainment of Normal Retirement Age; and

         (c) the complete discontinuance of contributions to the Plan, or the
             partial termination of the Plan (if the Participant is affected by
             such partial termination).

5.3      Application of Forfeitures

         A Participant whose employment shall terminate for any reason other
         than upon any of the events specified in Section 5.2 above shall
         forfeit the balance in his or her Account that is not vested at the
         time of his or her termination. All such forfeitures shall be
         determined as of the end of the Plan Year in which the Participant
         either receives a distribution of the vested portion of his or her
         Account or incurs a one-year Break in Service, whichever occurs first.
         Once so determined, all such forfeitures shall be used to reduce future
         Employer Contributions, except as is otherwise provided in Section 5.4.
         If a Participant has no vested interest in his or her Account at the
         time of his or her termination of employment with the Company or an
         Affiliate, the Participant shall be deemed to have received a full
         distribution of his or her Account on the date of such termination of
         employment and the non-vested amounts in his or her Account shall
         become forfeitures under the Plan.

                                       12

<PAGE>

5.4  Reemployment, Repayment and Restoration of Forfeiture

     If a former Participant whose termination resulted in a forfeiture under
     the provisions of Section 5.3 is reemployed as an Eligible Employee prior
     to the date he or she incurs five consecutive one-year Breaks in Service,
     such Participant may elect by giving 30 days' advance notice on the
     Appropriate Form (or such other period as may be prescribed by the
     Committee) to repay the Plan in cash, on any date within five years of such
     reemployment, the full dollar amount distributed in accordance with Section
     7. Such repayment will be allocated to such Participant's Account. In such
     event, the amount of the forfeiture (unadjusted by any gains or losses)
     will be restored and credited as of such date to such Participant's Account
     in such manner as the Committee shall deem appropriate pursuant to such
     uniform and non-discriminatory rules as it shall from time to time
     prescribe. The amount of the forfeiture which is restored will be derived
     from amounts forfeited and not yet applied to reduce future Employer
     Contributions, or, if such amounts are insufficient, any remaining
     forfeiture not so restored will be derived from additional Employer
     Contributions.

                                       13

<PAGE>

                                    SECTION 6
                             Investment of Accounts

6.1      Investment of Accounts

         All Accounts at all times shall be invested primarily in Company Stock.

 6.2     Diversification of Investments

         (a) Notwithstanding any other provision of this Plan, each "Qualified
             Participant" (as hereinafter defined) may elect, within the 90-day
             period following the close of each Plan Year during the
             Participant's "Qualified Election Period" (as hereinafter defined),
             to direct the Trustee as to the distribution, subject to this
             Section 6.3, of (i) 25% of the value of the "Qualified
             Participant's" Account attributable to Company Stock less (ii) the
             value of the Account previously distributed under an election
             pursuant to this paragraph (a) within the time determined under
             paragraph (b) below. With respect to the 25% limitation described
             in the preceding paragraph, a "Qualified Participant" may, within
             90 days after the close of the last Plan Year in the "Qualified
             Participant's" "Qualified Election Period," direct the Trustee to
             apply a percentage of 50%, rather than 25%.

         (b) Within 90 days after the close of each Plan Year during the
             "Qualified Election Period," the portion of a "Qualified
             Participant's" Account subject to the election described in
             paragraph (a) above shall be distributed in cash (or made available
             for distribution to such "Qualified Participant") or transferred to
             another qualified defined contribution plan maintained by the
             Company or Affiliate that offers at least three investment options
             other than Company Stock.

         (c) If the fair market value (determined at the Valuation Date
             immediately before the first day on which a "Qualified Participant"
             is eligible to make the election described in paragraph (a) above)
             of the Company Stock allocated to a "Qualified Participant's"
             account is $500 or less, then the Company Stock will be considered
             to be a de minimis amount that is not subject to the
             diversification requirement. For purposes of determining whether
             the de minimis amount is exceeded, Company Stock held in accounts
             of all Employee Stock Ownership Plans maintained by the Company or
             any Affiliate are considered to be held by the same plan.

         (d) For purposes of this Section 6.2, the terms "Qualified Participant"
             and "Qualified Election Period" shall have the following meanings:
             "Qualified Participant" means any Employee who has completed at
             least 10 years of participation under this Plan and has attained
             age 55. "Qualified Election Period" means the six-Plan Year period


                                       14

<PAGE>

             beginning with the first Plan Year in which the individual first
             became a Qualified Participant.


                                       15

<PAGE>

                                    SECTION 7
                    Distributions Upon Termination of Service

7.1      Distributions Upon Retirement, Death or Disability

         (a) Upon a Participant's termination of employment on account of his or
             her attainment of Normal Retirement Age, the total balance of his
             or her Account as of the Valuation Date determined in Section 8
             shall be distributed to him or her.

         (b) Upon a Participant's death, the total balance of all his or her
             Account as of the Valuation Date determined in Section 8 shall be
             distributed to his or her Beneficiary, in accordance with the
             provisions of Section 8.

         (c) Upon a Participant's Disability, the total balance of his or her
             Account as of the Valuation Date determined in Section 8 shall be
             distributed to him or her. At any time prior to a Participant's
             Normal Retirement Age, the Committee may, in its sole discretion,
             require a Participant who is receiving benefits on account of
             Disability to submit to a medical examination and/or to submit
             evidence of his or her continued eligibility for disability
             benefits under the Social Security Act, but not more often than
             semi-annually. In the event that a Participant's Disability ceases,
             no further payment shall be made from the Plan on account of such
             Disability. If an Employee returns to the employ of the Employer
             following the cessation of his or her Disability, such Employee's
             participation in the Plan shall immediately resume.

7.2      Distributions Upon Other Termination of Service

         If a Participant's employment is terminated for reasons other than on
         account of his or her attainment of Normal Retirement Age, Disability
         or death, the then vested portion (if any) of his or her Account as of
         the Valuation Date referred to in Section 8, shall be distributed to
         him or her or her in accordance with the provisions of Section 8. The
         Participant shall thereupon forfeit any remaining nonvested balance in
         his or her Account, if any, as of the Valuation Date, and such
         forfeited balance of each such Account shall be used to reduce future
         Employer Contributions.

                                       16

<PAGE>

                                    SECTION 8
                    Provisions Concerning Payment of Benefits

8.1      Payment of Benefits

         (a) In the event of his or her termination of employment with the
             Employer or any Affiliate by reason of (i) attainment of Normal
             Retirement Age, (ii) upon incurring a permanent Disability, or
             (iii) death, a Participant's entire vested balance in his or her
             Account as of the preceding Valuation Date shall be distributed in
             cash to him or her, or to his or her Beneficiary in the event of
             the Participant's death, in the form of a single lump sum payment,
             as soon as practicable, but in no event later than the last day of
             the Plan Year following the Plan Year in which the Participant
             terminates employment. Notwithstanding the foregoing, if the value
             of the vested balance in such Account as of such Valuation Date
             exceeds $50,000, the Participant's Account will be distributed in
             substantially equal annual installments over a five-year period
             instead of a single lump sum payment and if the Participant's
             vested balance in his or her Account exceeds $500,000, the
             five-year period shall be extended for one additional year (but not
             more than five additional years) for each $100,000 or fraction
             thereof by which the vested balance in his or her Account exceeds
             $500,000. These dollar amounts shall be adjusted at the same time
             and in the same manner as provided under Section 415(d) of the
             Code.

         (b) In the event of his or her termination of employment with the
             Employer or any Affiliate for any reason other than that described
             in paragraph (a) above, the distribution of the Participant's
             vested balance in his or her Account, determined as of the
             Valuation Date preceding such distribution date, and as of each
             such distribution date, will be as follows:

             (i)   If the value of the vested balance in such Account as of such
                   Valuation Date does not exceed, nor at any other time
                   exceeded, $5,000, the Participant's vested balance in his or
                   her Account shall be distributed in cash to him or her in the
                   form of a single lump sum payment, as soon as practicable,
                   but in no event later than the last day of the Plan Year
                   following the Plan Year in which the Participant terminates
                   employment.

             (ii)  If the value of the vested balance in such Account as of such
                   Valuation Date exceeds, or at any other time exceeded,
                   $5,000, but is less than $50,000 as of such Valuation Date,
                   his or her the vested balance in his or her Account, at his
                   or her election, may remain in the Trust Fund and will be
                   distributed in cash in a single lump sum payment on the day
                   the Participant reaches Normal Retirement Age, or sooner as
                   directed by the Participant. Alternatively, the Participant
                   may elect to receive distribution

                                       17

<PAGE>

                  of his or her interest in substantially equal annual
                  installments over a five year period.

           (iii)  If the value of the vested balance in such Account as of such
                  Valuation Date exceeds $50,000, his or her Account, at his or
                  her election, may remain in the Trust Fund and will be
                  distributed in cash in substantially equal annual installments
                  over a five-year period commencing on the day the Participant
                  reaches Normal Retirement Age. At the election of such
                  Participant, distributions may commence prior to the
                  Participant's Normal Retirement Age

           (iv)   If the event of a Paticipant's death before his or her Normal
                  Retirement Age, but after his or her termination of
                  employment, the entire vested balance that remains in his or
                  her Account as of the last Valuation Date shall be distributed
                  to his or her Beneficiary in the form of a single lump sum
                  payment, as soon as practicable, but in no event later than
                  the last day of the Plan Year following the Plan Year in which
                  the Participant dies.

      (c)  A Participant, or his or her Beneficiary in the event of the
           Participant's death, shall not have the right to demand a
           distribution of the Company Stock allocated to his or her Account,
           except as otherwise required by Code Section 409(h)(2)(B).

8.2   Identity of Payee

      If there is no person alive to accept receipt for any payment due under
      the Plan, the Committee shall direct that such payment or payments be made
      to the following persons in the following order of preference: the
      Participant's spouse, child or children per stirpes, parents, or the
      person or persons designated as his or her beneficiary under any group
      life insurance maintained by the Employer. The determination of the
      Committee as to the identity of the proper payee of any payment from the
      Trust Fund and the amount properly payable shall be conclusive, and
      payment in accordance with such determination shall constitute a complete
      discharge of all obligations on account thereof.

8.3   Latest Commencement of Benefits

      In no event shall a Participant's benefits under the Plan begin later than
      the 60th day after the close of the Plan Year in which the latest of the
      following events occur:

      (a)   The Participant attains Normal Retirement Age;

                                       18

<PAGE>

       (b)   the 10th anniversary of the date the Participant's participation in
             the Plan commences;

       (c)   the Participant's employment with the Company or any Affiliate is
             terminated.

8.4    Required Minimum Distributions

       Notwithstanding Sections 8.1 and 8.3 of the Plan, subject to Section
       1121(d)(4) of the Tax Reform Act of 1986 and Proposed Treasury Regulation
       Section 1.401(a)(9)-1:

       (a)   distributions to any Participant who is a 5% owner, as defined
             under Section 416 of the Code, shall begin not later than the April
             1 following the calendar year in which such Participant attains age
             70 1/2; and

       (b)   in the case of a Participant who is not a 5% owner, distributions
             shall begin not later than the April 1 following the later of the
             calendar year in which the Participant attains age 70 1/2, or his
             or her termination of employment with the Employer or an Affiliate.

       This Section 8.4 shall only apply to a Participant who remains in the
       employment of the Employer beyond the calendar year in which he or she
       reaches age 70 1/2 and who is required to receive distribution of his or
       her Account in the form of annual installments. Any distributions under
       this Plan shall be adjusted to meet the requirements of Section 401(a)(9)
       of the Code and the regulations thereunder. Thus, the entire interest of
       each Participant shall be distributed, beginning not later than the
       required beginning date, as described above and in accordance with
       regulations, over the life of the Participant or over the life of the
       Participant and Beneficiary (or over a period not extending beyond the
       life expectancy of the Participant or the life expectancy of the
       Participant and Beneficiary). In addition, any distribution required
       under the incidental death benefit rule of Section 401(a)(9)(G) of the
       Code shall be treated as distribution required under the preceding
       sentence.

8.5    Direct Rollover From the Plan

       Notwithstanding any provision of the Plan to the contrary that would
       otherwise limit a distributee's election under this Section, a
       "Distributee" may elect, at the time and in the manner prescribed by the
       Committee, to have any portion of an "Eligible Rollover Distribution"
       paid directly to an "Eligible Retirement Plan" specified by the
       distributee in a "Direct Rollover" (as such terms are defined below).

                                       19

<PAGE>

Definitions:

(a)  Eligible Rollover Distribution: An Eligible Rollover Distribution is any
     distribution of all or any portion of the balance to the credit of the
     distributee, except that an Eligible Rollover Distribution does not
     include:

     (i)   any distribution that is one of a series of substantially equal
           periodic payments (not less frequently than annually) made for the
           life (or life expectancy) of the distributee or the joint lives (or
           joint life expectancies) of the distributee and the distributee's
           designated beneficiary, or for a specified period of ten years or
           more;

     (ii)  any distribution to the extent such distribution is required under
           Section 401(a)(9) of the Code; and

     (iii) the portion of any distribution that is not includable in gross
           income (determined without regard to the exclusion for net unrealized
           appreciation with respect to employer securities).

(b)  Eligible Retirement Plan: An Eligible Retirement Plan is an individual
     retirement account described in Section 408(a) of the Code, an individual
     retirement annuity described in Section 408(b) of the Code, an annuity plan
     described in Section 403(a) of the Code, or a qualified trust described in
     Section 401(a) of the Code, that accepts the distributee's Eligible
     Rollover Distribution. However, in the case of an Eligible Rollover
     Distribution to the surviving spouse, an Eligible Retirement Plan is an
     individual retirement account or individual retirement annuity.
     Notwithstanding anything herein to the contrary, two Eligible Retirement
     Plans may be designated with respect to any Eligible Rollover Distribution.

(c)  Distributee: A distributee includes an Employee or former Employee. In
     addition, the Employee's or former Employee's spouse or former spouse who
     is the alternate payee under a qualified domestic relations order, as
     defined in Section 414(p) of the Code, are distributees with regard to the
     interest of the spouse or former spouse.

(d)  Direct Rollover: A direct rollover is a payment by the Plan to the Eligible
     Retirement Plan specified by the distributee. Notwithstanding anything
     herein to the contrary, two direct rollovers may be made with respect to
     any Eligible Rollover Distribution.

                                       20

<PAGE>

8.6  Non-Alienation of Benefits

     Except as otherwise provided by law, no benefit, interest or payment under
     the Plan shall be subject in any manner to anticipation alienation, sale,
     transfer, assignment, pledge, encumbrance or charge, whether voluntary or
     involuntary, and no attempt to so anticipate, alienate, sell, transfer,
     assign, pledge, encumber or charge the same be valid nor shall any such
     benefit, interest or payment be in any way liable for or subject to the
     debts, contracts, liabilities, engagements or torts of the person entitled
     to such benefit, interest, or payment or subject to attachment,
     garnishment, levy execution or other legal or equitable process. Except as
     otherwise permitted by Code Section 409(h)(2) or other applicable law, no
     shares of Company Stock held or distributed by the Trustee may be subject
     to a put, call or other option, or buy-sell or similar arrangement. The
     provisions of this section shall continue to be applicable to shares of
     Company Stock even if the Plan ceases to be an employee stock ownership
     plan under Code Section 4975(e)(7). Notwithstanding the foregoing, the
     creation, assignment, or recognition of a right to any benefit payable with
     respect to a Participant pursuant to a "qualified domestic relations order"
     (as defined in Section 414(p) of the Code) shall not be treated as an
     assignment or alienation prohibited by this Section 8.6. A domestic
     relations order will not be considered as a "qualified domestic relations
     order" if it: (i) requires the Plan to provide a type or form of benefit
     not otherwise provided under the Plan, or (ii) requires the Plan to provide
     increased benefits (determined on the basis of actuarial value), or (iii)
     requires the payment of benefits to an alternate payee under another order
     previously determined to be a "qualified domestic relations order." A
     domestic relations order shall not be treated as failing to meet the
     requirements of subpart (i) of the preceding sentence solely because it
     requires payment of benefits on or after the date on which the Participant
     attains early retirement age (as defined in Section 414(p)(4)(B) of the
     Code) under the Plan whether or not the Participant actually retires on
     that date. During any period in which the Committee is determining whether
     an order is a "qualified domestic relations order," no benefits which are
     in dispute shall be paid hereunder, except as may be required by the Code.
     Any other provision of the Plan to the contrary notwithstanding, the
     Committee is authorized, pursuant to such uniform and nondiscriminatory
     rules as it shall establish which shall be consistent with applicable law
     and the terms of the applicable qualified domestic relations order, to cash
     out benefits to which alternate payees may be entitled prior to the date
     such benefits would otherwise become payable in accordance with the
     applicable provisions of the Plan.

                                       21

<PAGE>

                                   SECTION 9
                           Administration of the Plan

9.1  Named Fiduciary and Plan Administrator

     The "Named Fiduciary", as that term is defined in Section 402(a)(2) of
     ERISA, shall be as follows:

     (a)  The Trustee, with respect to the management and investment of the
          assets of the Plan and the payment of benefits to Participants;

     (b)  The Committee, with respect to the administration and operation of the
          Plan, and for the purposes of determining appeals with respect to
          denied claims for benefits.

     The authority of each Named Fiduciary in his or her or its designated area
     of responsibility, as aforesaid, shall be exclusive, and no Named Fiduciary
     shall have either authority or responsiblility to exercise any discretion
     or control other than as specifically delegated to him or her or it under
     this Plan or the Trust Agreement.

     The Company shall be the "administrator" and "plan administrator" with
     respect to the Plan, as those terms are defined in Section 3(16)(A) of
     ERISA and in Section 414(g) of the Code.

9.2  Committee

     The Board of Directors shall appoint a Committee of not less than three
     members designated by the Board of Directors who shall serve at the
     pleasure of the Board of Directors. The Committee, in its sole and absolute
     discretion, from time to time, may authorize and designate any person or
     persons to act on behalf of the Committee. The Secretary of the Board of
     Directors shall from time to time notify the Trustee of the appointment of
     members of the Committee and of any other person designated to act on
     behalf of the Committee, together with specimens of their signatures, and
     for all purposes hereunder the Trustee shall be entitled to conclusively
     rely upon the identity of the members constituting the Committee and the
     identity of such other person or persons as disclosed by the last filed of
     such certificates. The Committee shall elect one of its members as Chairman
     and one of its members as Secretary and may also appoint such other
     officers as it deems necessary. A majority of the members of the Committee
     shall constitute a quorum for the transaction of business and all
     resolutions or other actions of the Committee at any meeting shall be by a
     vote of a majority of those present at such meeting; provided, however, any
     action required or permitted to be taken at any meeting of the Committee
     may be taken without a meeting if prior to such action a written consent
     thereto is signed by a majority of the members of the Committee then in

                                       22

<PAGE>

     office and such written consent is filed with the minutes of the Committee.
     If there are two or more Committee members, no member shall act upon any
     question pertaining solely or primarily to him or herself, and the other
     member or members shall alone make any determination required by the Plan
     in respect thereof. The Committee may authorize any one or more of its
     members to execute any document on behalf of the Committee, in which event
     the Committee shall notify the Trustee in writing of such action and the
     name or names of its member or members so designated. The Trustee
     thereafter shall accept and rely upon any document executed by such member
     or members as representing action by the Committee until the Committee
     shall file with the Trustee a written revocation of such designation. No
     bond or other security shall be required of any member of the Committee as
     such, except as ERISA may otherwise require.

9.3  Rules and Regulations

     (a)  The Committee from time to time may establish rules and regulations
          for the administration for the Plan, provided that such regulations
          shall be consistent with the provisions hereof. The Committee shall
          have the exclusive right to interpret the Plan provisions and to
          exercise discretion where necessary or appropriate in the
          interpretation and administration of the Plan and to decide any and
          all matters arising thereunder or in connection with the
          administration of the Plan, and it shall endeavor to act, whether by
          general rules or by particular decisions, so as not to discriminate in
          favor of any person or class of person. Such decisions, actions and
          records of the Committee shall be conclusive and binding upon the
          Company, the Employer and all persons having or claiming to have any
          right or interest in or under the Plan. Without limiting the
          generality of the foregoing, the Committee may adopt such regulations
          with respect to the signature by a Participant and/or the beneficiary
          of a Participant, to any directions or other papers to be signed by a
          Participant and similar matters the Committee may determine to be
          necessary or advisable in view of orderly Plan administration or the
          laws of any State or States.

     (b)  To facilitate payments to Participants, the Committee may establish
          and maintain one or more checking accounts in the name of the Plan and
          designate the person or persons authorized to sign checks on such
          accounts. Funds to be placed in such accounts shall be transferred
          thereto by the Trustee on instructions from the Committee. If a
          Participant or Beneficiary is physically or mentally incapable of
          receiving and acknowledging receipt of benefit payments due under the
          Plan, the Committee, in its discretion, may cause such payments to be
          made by the Trustee to such institution, guardian, trustee,
          conservator, or receiver or other person for the use, benefit or
          support, of the said Participant or Beneficiary without the
          interposition of a guardian, as the Committee may select.

                                       23

<PAGE>

     (c)  The Committee shall at least annually transmit to each Participant a
          statement in such form as the Committee shall determine setting forth
          the value of such Participant's Account. Such statements shall be
          deemed to have been accepted as correct unless written notice to the
          contrary is received by the Committee within thirty days after
          delivery of such statement to the Participant. Other reports and
          descriptions required by ERISA shall be prepared and distributed by
          the Committee or by the Company.

     (d)  No director, officer or employee of the Company, or of any Employer
          shall be personally liable for any act or omission to act in
          connection with the operation or administration of the Plan other than
          through his own willful misconduct or gross negligence, except as
          ERISA may otherwise require.

     (e)  The Committee shall direct the Trustee to sell Company Stock allocated
          to a Participant's Account in the event such Participant elects a cash
          distribution. Such sales shall either be in public market or private
          transactions. If sold to the Company, the price of Company Stock shall
          be the fair market value of Company Stock, as determined by the
          Committee (and as accepted by the Trustee), for all purposes under the
          Plan based upon the valuation of an independent appraiser (within the
          meaning of Section 401(a)(28)(C) of the Code). The Committee also
          shall have the right to direct the Trustee to borrow in order to
          purchase Company Stock and to direct the Trustee as otherwise provided
          herein.

9.4  Voting Company Stock

     (a)  General Rule: Except as provided in subsection (b), the Trustee shall
          vote any shares of Company Stock held by the Trust Fund.

     (b)  Major Matters: With respect to any corporate merger or consolidation,
          recapitalization, reclassification, liquidation, dissolution, sale of
          substantially all assets of a trade or business of the Company, or any
          other matter specified in regulations issued under Code Section
          409(e)(3), the Trustee shall pass through to Participants the voting
          rights relating to Company Stock allocated to the Participants'
          Accounts.

     (c)  Procedures: If a pass-through of voting rights is required under
          subsection (b), the following procedures shall be followed:

          (i)  Before each annual or special meeting of the stockholders of the
               Company and contemporaneously with the notice to stockholders of
               the Company, the Company shall cause to be sent to each
               Participant (or in the event of his or her death, his or her
               Beneficiary) a copy of the proxy solicitation

                                       24

<PAGE>

                material therefore, together with a form requesting confidential
                instructions to the Trustee or Transfer Agent on how to vote the
                number of shares of Company Stock credited to such Participant's
                Account as of the Valuation Date next preceding the record date
                for each such meeting.

          (ii)  Upon receipt of instruction from each Participant or Beneficiary
                as to how to vote his or her number of whole shares of Company
                Stock in the Trust, the Trustee or Transfer Agent shall vote
                such shares in accordance with such instructions.

          (iii) Instructions received from individual Participants or
                Beneficiaries by the Trustee or Transfer Agent shall be held in
                the strictest confidence and shall not be divulged or released
                to any person, including officers or employees of the Company.

          (iv)  The Trustee or Transfer Agent may not vote in person or by proxy
                any shares of Company Stock for which voting instructions shall
                not have been received at the time of any meeting.

9.5  Claims for Benefits

     For purposes of the Plan, a claim for benefits is a written application for
     benefits filed with the Committee on the Appropriate Form. In the event
     that any Participant or other payee claims to be entitled to a benefit
     under the Plan, and the Committee determines that such claim should be
     denied in whole or in part, the Committee shall, in writing, notify such
     claimant within 90 days of receipt of such claim that his claim has been
     denied, setting forth the specific reasons for such denial. Such
     notification shall;

     (a)  be written in a manner reasonably expected to be understood by such
          Participant or other payee,

     (b)  set forth the pertinent sections of the Plan relied on, and

     (c)  set forth an explanation of how the claimant can obtain review of such
          denial.

     Within 60 days after the mailing or delivery by the Committee of such
     notice, such claimant may request, by mailing or delivery of written notice
     to the Committee, a review and/or hearing by the Committee of the decision
     denying the claim. If the claimant fails to request such a review and/or
     hearing within such 60 day period, it shall be conclusively determined for
     all purposes of this Plan that the denial of such claim by the Committee is
     correct. If such claimant requests a hearing within such 60 day period, the
     Committee shall designate a time (which time shall be not less than seven
     nor more than 60 days from the date of such claimant's notice to the
     Committee) and a place for such hearing, and shall

                                       25

<PAGE>

     promptly notify such claimant of such time and place. If only a review is
     requested, the Participant or other payee shall have 30 days after filing a
     request for review to submit additional written material in support of the
     claim. After such review and/or hearing, the Committee shall determine
     whether such denial of the claim was correct and shall notify such claimant
     in writing of its determination. If such determination is favorable to the
     claimant, it shall be binding and conclusive. If such determination is
     adverse to such claimant, it shall be binding and conclusive unless the
     claimant notifies the Committee within 90 days after the mailing or
     delivery to him or her by the Committee of its determination that he
     intends to institute legal proceedings challenging the determination of the
     Committee, and actually institutes such legal proceeding within 180 days
     after such mailing or delivery.

9.6  Records and Reports

     The Committee shall keep a record of its proceedings and acts and shall
     keep such books of account, records and other data as may be necessary for
     the proper administration of the Plan. The Committee shall notify the
     Trustee and the Company of any action taken by it and, when required, shall
     notify any other interested person. The Committee shall make its records
     available to the Company or to any Participant for examination during
     business hours at the Company's principal place of business, except that a
     Participant shall be allowed to examine only such records as pertain to him
     or herself.

9.7  Required Information

     The Company, Participant or Beneficiary or any other person entitled to
     benefits from the Plan shall furnish the Committee with any information or
     proof requested by the Committee and reasonably required for the proper
     administration of the Plan. Failure on the part of any Participant,
     Beneficiary or other to comply with such request, within a reasonable
     period of time and in good faith, shall be sufficient grounds for denying
     or discontinuing benefits to such Participant, Beneficiary or other person.

9.8  Payment of Expenses

     Except as otherwise required by law or agreed upon with the Company, the
     members of the Committee shall serve without bond and without compensation.
     The expenses of the Committee shall be deemed administrative expenses which
     may be paid from the Trust Fund, unless paid by the Company in its
     discretion. All reasonable expenses of administering the Plan and Trust
     shall be charged to and paid out of the Trust Assets. The Company, however,
     may pay all or any portion of such expenses directly, and payment of
     expenses by the Company shall not be deemed to be Employer Contributions.

                                       26

<PAGE>

9.9  Indemnification

     Except to the extent required by ERISA, no member of the Committee shall be
     liable for any act, omission, determination, construction or communication
     made by him or herself, the Committee or by any other member thereof, and
     the Company hereby agrees to indemnify and save harmless each person now
     or hereafter acting as a member of the Committee from all loss or damage
     that may or might result from his acts as such member, except to the extent
     that any liability is imposed as a result from his acts as such member,
     except to the extent that any liability is imposed as a result of the
     member's gross negligence or willful misconduct. Nothing herein shall
     prohibit the Company from purchasing insurance to indemnify any such member
     for such liability.

                                       27

<PAGE>

                                   SECTION 10
                          Management of the Trust Fund

10.1 Trustee

     All contributions to the Trust Fund shall be made to, and held in trust by,
     the Trustee of the Plan, who shall be appointed from time to time by the
     Board of Directors by appropriate instrument, with such powers in the
     Trustee as to investment, reinvestment, control and disbursement of the
     funds as may be provided in the Trust Agreement. The Board of Directors may
     remove any Trustee at any time, upon reasonably notice and upon such
     removal or upon the resignation of any Trustee the Board of Directors
     shall designate a successor Trustee. The Trustee and the Company may by
     mutual agreement in writing and in accordance with the Trust Agreement
     arrange for the delegation by the Trustee to others of any functions.

10.2 Trust Fund

     All assets held by the Trustee under the Plan shall be held in trust for
     the exclusive benefit of Participants and their Beneficiaries under the
     Plan, and no part of the corpus or income shall revert to the Company or
     the Employer or be used for, or diverted to, purposes other than for the
     exclusive benefit of Participants and their Beneficiaries under the Plan or
     for the payment of the expenses of the Trust Fund, except as provided by
     Section 403(c)(2) or ERISA. Except to the extent expressly provided in the
     Plan, no such person, nor any other person, shall have any interest in or
     right to any part of the earnings of the Trust Fund, or any rights in, to
     or under the Trust Fund or any part of its assets.

                                       28

<PAGE>

                                   SECTION 11
                 Amendment, Merger and Termination of the Plan

11.1  Amendment

      This Plan may be wholly or partially amended or otherwise modified at any
      time by the written action of the Board of directors, provided, however,
      that:

      (a)  no amendment or modification may be made which would permit any part
           of the corpus or income of the Trust to be used for or diverted to
           purposes other than for the exclusive benefit of the Participants and
           their Beneficiaries under the Plan or for the payment of the expenses
           of the Trust Fund;

      (b)  no amendment or modification may be made which would adversely affect
           the Account balances of the Participants and their Beneficiaries
           under the Plan; and

      (c)  no amendment or modification may be made which shall increase the
           duties or liabilities of the Trustee or of the Committee without
           written consent of the party so affected.

11.2  Merger, Consolidated or Sale of the Employer

      (a)  If the Employer is merged or consolidated with another organization,
           or if the Employer is sold, sells its assets, or is dissolved, any
           successor organization may continue the Plan with the consent of the
           Board of Directors. If the Plan is continued, the Committee may
           transfer assets of the Trust Fund attributable to the Participants
           employed by such Employer to a separate trust fund maintained by the
           successor organization. If the successor organization maintains a
           comparable plan, the Committee may transfer assets of the Trust Fund
           attributable to such Participants to the trust fund of the comparable
           plan. If the assets of the Trust Fund are not transferred to a
           successor trust fund, the Committee may consider the Plan terminated
           for such Participants.

      (b)  In the case of any merger or consolidation with, or transfer of
           assets or liabilities to, any other plan, each Participant in the
           Plan will (if the Plan is then terminated) receive a benefit
           immediately after the merger, consolidation or transfer which is
           equal to or greater than the benefit he would have been entitled to
           receive immediately before the merger, consolidation, or transfer (if
           the Plan had then terminated).

                                       29

<PAGE>

11.3   Suspension or Termination

       (a)   The Board of Directors, at any time, may suspend Employer
             Contributions in whole or in part. The suspension of Employer
             Contributions shall not in itself constitute a termination of the
             Plan.

       (b)   Any Employer, at any time, may withdraw from the Plan by filing
             with the Committee a certified copy of the resolution of its board
             of directors authorizing the termination or discontinuance. A
             complete and permanent discontinuance of Employer contributions
             shall be treated as a termination of the Plan.

       (c)   If the Plan is terminated, no further contributions shall be made
             by the Employer, and the Accounts of each Participant shall be
             applied for his or her (or his or her Beneficiary) benefit either
             by payment in cash or in kind, or by the continuation of the Trust
             Fund in accordance with the Trust Agreement and the provisions of
             the Plan as though the Plan were otherwise in full force and
             effect. Distributions shall be made in lump sum payments.

11.4   Vesting and Maintenance of Accounts

       Upon termination or partial termination of the Plan or the complete
       discontinuance of contributions under the Plan, the Account of each
       Participant shall be fully vested and non-forfeitable; provided, however,
       that in the event of a partial termination, the non-forfeitable rights
       shall be applicable only to the portion of the Plan that is terminated.
       Until distributed to the Participant in accordance with Section 11.3,
       each participant's Account shall continue to be valued in accordance with
       the provisions of Section 5. For purposes of such valuations, the date as
       of which contributions are discontinued or the date set forth as the
       termination date shall be deemed a Valuation Date. Included in any such
       valuation shall be expenses incurred in effectuating such termination,
       partial termination or discontinuance (such as the fees and retainers of
       the Plan's Trustee, actuary, accountant, custodian, counsel,
       administrator or other specialist).

                                       30

<PAGE>

                                   SECTION 12
                         Adoption of Plan by Affiliate

12.1  Adoption

      Any Affiliate may adopt this Plan with the approval of the Board of
      Directors and thereby come within the definition of Employer. A list of
      Employers is contained in Appendix A of the Plan. An Affiliate is required
      to execute a signature page to adopt the Plan. Such signature pages are
      attached to the Plan as Appendix B. The Board of Directors reserves the
      right to withdraw any Employer from the Plan. The contributions to be made
      pursuant to Section 3.2 by each Employer shall be determined by the
      Company.

12.2  Modification of Adoption

      If any Affiliate that has come within the definition of Employer pursuant
      to Section 12.1 subsequently adopts a different plan or amends this Plan
      with the approval of the Board of Directors for all or part of its
      employees or if any such Affiliate withdraws or is withdrawn from the
      Plan, the Committee shall determine the equitable share of the funds held
      by the Trustee which shall be allocated to the Employees of such Affiliate
      who are thereby affected. If a separate plan is being continued for such
      Employees, such Affiliate shall designate a successor funding agent under
      a separate instrument to whom such allocable funds shall be transferred
      with respect to all or the specified classifications of its Employees, as
      the case may be, unless the Board of Directors shall determine that such
      Affiliate and its affected Employees may, upon prior action of such
      Affiliate, continue to participate in the trust maintained in connection
      with this Plan. If the Plan is discontinued with respect to all or part of
      such Affiliate's Employees, such allocable funds shall be allocated with
      respect to each Employee affected, and shall be applied, pursuant to
      Section 11.3.

                                       31

<PAGE>

                                   SECTION 13
                        In Event Plan Becomes Top-Heavy

13.1   Purpose and Limited Application of this Section

       The purpose of this Section 13 is to conform to the requirement of
       Section 401(a)(10)B) of the Code that the Plan contains provisions (a)
       which will take effect if it becomes Top-Heavy and (b) which meet the
       requirements of Section 416 of the Code.

13.2   Special Definitions

       For purposes of this Section 13, the following terms, in addition to
       those defined in Section 1 shall have the following meanings:

       (a)   "Determination Date" means, with respect to any Plan Year, the last
       Valuation Date of the preceding Plan Year.

       (b)   "Key Employee" means any Employee or former Employee (and the
       beneficiaries of such Employee) who at any time during the determination
       period was an officer of the Employer if such individual's annual
       compensation exceeds 150 percent of the dollar limitation under Section
       415(c)(1)(A) of the Code, an owner (or considered an owner under Section
       318 of the Code) of one of the ten largest interests in the Employer if
       such individual's compensation exceeds 100 percent of such dollar
       limitation, a 5-percent owner of the Employer, or a 1-percent owner of
       the Employer who has an annual compensation of more than $150,000. The
       determination period is the Plan Year containing the Determination Date
       of the 4 preceding Plan years.

       The determination of who is a `Key Employee' will be made in accordance
       with Section 416(i)(1) of the Code and the regulations thereunder.

       (c)   "Permissive Aggregation Group" means, with respect to a given Plan
       Year, this Plan and all other plans of the Employer or Affiliates (other
       than those included in the Required Aggregation Group) which, when
       aggregated with the plans in the Required Aggregation Group, continue to
       meet the requirement of Sections 401(a)(4) and 410 of the Code.

       (d)   "Present Value of Accounts" means, as of a given Determination
       Date, the sum of the Participant's Accounts under the Plan as of such
       Valuation Date. The Determination Date of the Present Value of Accounts
       shall take into consideration distributions made to or on behalf of the
       Participant in the Plan Year ending on the Determination Date and the
       four preceding Plan Years, but shall not take into consideration the
       Accounts of any

                                       32

<PAGE>

     Participant who has not performed services for the Employer during the
     five-year period ending on the Determination Date.

     (e)  "Required Aggregation Group" means with respect to a given Plan Year,
     (A) this Plan, (B) each other plan of the Employer and Affiliates in which
     a Key Employee is a participant, and (C) each other plan of the Employer
     and Affiliates which enables a plan described in (A) or (B) to meet the
     requirements of Sections 401(a)(4) and 410 of the Code.

     (f)  "Top-Heavy" means, with respect to the Plan for a Plan Year:

               (1)  that the Present Value of Accounts of Key Employees exceeds
                    60% of the Present Value of Accounts of all Participants; or

               (2)  the Plan is part of a Required Aggregation Group and such
                    Required Aggregation Group is a Top-Heavy Group, unless the
                    Plan or such Top-Heavy Group is itself part of a Permissive
                    Aggregation Group which is not a Top-Heavy Group.

     (g)  "Top-Heavy Group" means, with respect to a given Plan Year, a group of
     Plans of the Employer and Affiliates which, in the aggregate, meet the
     requirements of the definition contained in Section 416(g)(2)(B) of the
     Code.

13.3 Special Top-Heavy Rules

     Notwithstanding any other provision of the Plan to the contrary, the
     following provisions of this Section 13.3 shall automatically become
     operative and shall supersede any conflicting provisions of the Plan if, in
     any Plan Year, the Plan is Top-Heavy.

     (a)  The minimum Employer contribution during the Plan Year on behalf of a
          Participant who is an Eligible Employee on the last day of such Plan
          Year and is not a Key Employee (regardless of such Employee's
          employment during such year shall be equal to the lesser of (1) 3% of
          such Participant's Section 415 compensation (as defined in Section
          3.4); or (2) the percentage of compensation at which Employer
          Contributions are made (or required to be made) under the Plan on
          behalf of the Key Employee for whom such percentage is the highest.

     (b)  A Participant who has completed three or more Years of Service with
          the Employer shall be 100% vested in all his Accounts.

     (c)  In order to comply with the requirements of Section 426(h) of the
          Code, in the case of a Participant who is or has also participated in
          a defined benefit plan of the Company or an Affiliate in any Plan Year
          in which the Plan is Top-Heavy, there

                                       33

<PAGE>

          shall be imposed under such defined benefit plan the following
          limitation in addition to any limitation which may be imposed as
          described in Section 3.4. In any such year, for purposed of satisfying
          the aggregate limit on contributions and benefits imposed by Section
          415(e) of the Code, benefits payable from the defined benefit plan
          shall, except as hereinafter described, be reduced so as to comply
          with a limit determined in accordance with Section 415(e) of the Code,
          but with the number "1.0" substituted for the number "1.25" in the
          "defined benefit plan fraction" (as defined in Section 415(e)(2) of
          the Code) and in the "defined contribution plan fraction" (as defined
          in Section 415(e)(3) of the Code). Notwithstanding the foregoing, if
          the application of the additional limitation set forth in this
          subsection (c) would result in the reduction of accrued benefits of
          any Participant under the defined benefit Plan, such additional
          limitation shall not become operative, so long as (1) no additional
          Employer contributions, forfeitures, or voluntary nondeductible
          contributions are allocated to such Participant's accounts under any
          defined contribution plan maintained by the Employer and Affiliates.
          Accordingly, in any Plan Year that the Plan is Top-Heavy, no
          additional benefits shall accrue under the defined benefit plan on
          behalf of any Participant whose overall benefits under the defined
          benefit plan otherwise would be reduced in accordance with the
          limitation described in this subsection (c).

     (d)  Solely for the purpose of determining if the Plan, or any other plan
          included in a Required Aggregation Group of which this Plan is a part
          is Top-Heavy, the accrued benefit of a Participant other than a Key
          Employee shall be determined under (1) the method, if any, that
          uniformly applies for the accrual purposes under all plans maintained
          by the Employer or Affiliate, or (2) if there is no such method, as if
          such benefit accrued not more rapidly than the slowest accrual rate
          permitted under the fractional accrual rate of Code section
          411(b)(1)(C).

     (e)  In the event that Congress should provide by statute, or the Treasury
          Department should provide by regulation or ruling, that the
          limitations provided in this Section 15 are no longer necessary for
          the Plan to meet the requirements of Section 401 of the Code or other
          applicable law then in effect, such limitations shall become void and
          shall no longer apply, without the necessity of further amendment to
          the Plan.

                                       34

<PAGE>

                                   SECTION 14

                            Miscellaneous Provisions

14.1 Limitation of Liability

     Except as otherwise provided in accordance with ERISA, as a condition of
     participation in the Plan, each employee agrees that neither the Company,
     any Employer, the Committee, nor the Trustee shall in any way be subject to
     any legal liability for any reason in connection with the Plan and Trust
     Fund or their operation, except for its or their own gross negligence or
     willful misconduct, and each such Employee hereby releases the Company and
     the Employers, their officers and agents, the Committee and the Trustee
     from any and all such liability.

14.2 Identity of Payee

     The determination of the Committee as to the identity of the proper payee
     of any benefit under the Plan and amount of such benefit properly payable
     shall be conclusive, and payment in accordance with such determination
     shall constitute a complete discharge of all obligations on account of such
     benefit.

14.3 Applicability

     Except as is otherwise provided in ERISA all questions pertaining to the
     construction, regulation, validity and effect of the provisions of the Plan
     shall be determined in accordance with the laws of the State of New Jersey.

14.4 Limitation of Rights

     Neither the establishment of the Plan, not any modification thereof, nor
     the creation of any fund, trust or account, nor the payment of any benefits
     shall be construed as giving any Participant or any other person any legal
     or equitable right against the Company, an Employer, the Committee or the
     Trustee, unless such right shall be specifically provided for in the Plan
     or granted by affirmative action of the Committee or the Company in
     accordance with the terms and provisions of the Plan; or as giving any
     Participant or any other employee of the Employer the right to be retained
     in the service of the Employer; and all Participants and other employees
     shall remain subject to discharge to the same extent as if the Plan had
     never been adopted.

14.5 Plan not a Condition of Employment

     The adoption and maintenance of the Plan shall not be deemed to constitute
     a contract between the Employer and any Participant, or to be consideration
     for, or an inducement or condition of, the employment of any person.
     Nothing herein contained shall be deemed to

                                       35

<PAGE>

       give to any Participant the right to be retained in the employ of the
       Employer or to interfere with the right of the Employer to discharge any
       Participant at any time.

14.6   Assumption of Risk by Participants

       Each Participant assumes all risk connected with any decrease in the
       market price of any securities in the fund, and such fund shall be the
       sole source of payments to be made under this Plan.

14.7   Uniform Administration

       Whenever, in the administration of the Plan, any action is required by
       the Employer or the Committee, including, but not by way of limitation,
       action with respect to eligibility or classification of Employees,
       contributions or benefits, such action shall be uniform in nature as
       applied to all persons similarly situated and no such action shall be
       taken which will discriminate in favor of Participants who are Highly
       Compensated Employees.

14.8   Severability

       If any provision of the Plan or any regulation adopted thereunder is
       deemed or held to be unlawful or invalid for any reason, the remaining
       provisions of the Plan or regulations thereunder shall not be adversely
       affected unless such determination shall render it impossible or
       impractical for the continued operation of the Plan. In such event, the
       appropriate parties shall immediately adopt a new provision or regulation
       to replace the one held unlawful or invalid.

14.9   Titles and Headings

       The titles and headings of the Sections of this Plan are for convenience
       of reference only, and in the event of any conflict, the text of this
       Plan, rather such titles or headings, shall control.

                                       36

<PAGE>

                                   SECTION 15

                                   Execution

     To record the adoption of the Plan, the Company has caused it to be
executed on this 4/th/ day of January, 1999.


                                               MANTECH INTERNATIONAL CORPORATION

                                               By: /s/ GEORGE J. PEDERSEN
                                                  ------------------------------

                                       37

<PAGE>

                                   APPENDIX A

                         Participating Employers in the

        ManTech International Corporation Employee Stock Ownership Plan

Participating Employer                            EIN            Effective Date

ManTech International Corporation                 22-1852179

ManTech Systems Engineering Corporation           52-1396237

ManTech Test Systems, Inc.                        54-1865918

ManTech Test Systems Integration Corporation      54-1871905

ManTech Test Systems Solutions Corporation        54-1030125

ManTech Environmental Technology, Inc.            54-1554099

ManTech Environmental Research Services Corp.     54-1661370

NSI Environmental Solutions, Inc.                 52-1714389

ManTech Environmental Corporation                 54-1791879

ManTech Design and Developmental Corporation      52-2001818

ManTech Advanced Systems International, Inc.      52-1396243

ManTech Telecommunications & Info. Systems Co.    52-1279373

ManTech Germany Systems Corporation               54-1908709

ManTech China Systems Corporation                 54-1904240

ManTech Y2K Solutions, Inc.                       (EIN Application Submitted)

<PAGE>

                                   APPENDIX B

                Execution by: ManTech International Corporation

      To record the adoption of the Plan, ManTech International Corporation has
caused it to be executed on this 4/th/ day of January, 1999.


                                          PARTICIPATING EMPLOYER:

                                          By: /s/ JOHN A. MOORE, JR.
                                             -----------------------

<PAGE>

                                APPENDIX B

              Execution by: ManTech Systems Engineering Corporation

      To record the adoption of the Plan, ManTech Systems Engineering
Corporation has caused it to be executed on this 4/th/ day of January, 1999.


                                          PARTICIPATING EMPLOYER:

                                          By: /s/  JOHN A. MOORE, JR.
                                             ------------------------

<PAGE>

                                   APPENDIX B

                    Execution by: ManTech Test Systems, Inc.

      To record the adoption of the Plan, ManTech Test Systems, Inc. has caused
it to be executed on this 4/th/ day of January, 1999.


                                          PARTICIPATING EMPLOYER:

                                          By: /s/  JOHN A. MOORE, JR.
                                             ------------------------

<PAGE>

                                   APPENDIX B


             Execution by: ManTech Systems Integration Corporation


     To record the adoption of the Plan, ManTech Systems Integration Corporation
has caused it to be executed on this 4/th/ day of January, 1999.



                                        PARTICIPATING EMPLOYER:


                                        By:   /s/ JOHN A. MOORE, JR.
                                           -------------------------------

<PAGE>

                                   APPENDIX B


              Execution by: ManTech Systems Solutions Corporation


     To record the adoption of the Plan, ManTech Systems Solutions Corporation
has caused it to be executed on this 4/th/ day of January, 1999.



                                        PARTICIPATING EMPLOYER:


                                        By: /s/ JOHN A. MOORE, JR.
                                           ---------------------

<PAGE>

                                   APPENDIX B

              Execution by: ManTech Environmental Technology, Inc.

     To record the adoption of the Plan, ManTech Environmental Technology, Inc.
has caused it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/ JOHN A. MOORE, JR.
                                                 ----------------------

<PAGE>

                                   APPENDIX B

        Execution by: ManTech Environmental Research Services Corporation

     To record the adoption of the Plan, ManTech Environmental Research Services
Corporation has caused it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/  JOHN A. MOORE, JR.
                                                 -----------------------

<PAGE>

                                   APPENDIX B

                 Execution by: NSI Environmental Solutions, Inc.

     To record the adoption of the Plan, NSI Environmental Solutions, Inc. has
caused it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/ JOHN A. MOORE, JR.
                                                 ----------------------

<PAGE>

                                   APPENDIX B

                 Execution by: ManTech Environmental Corporation

     To record the adoption of the Plan, ManTech Environmental Corporation has
caused it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/  JOHN A. MOORE, JR.
                                                 -----------------------

<PAGE>

                                   APPENDIX B

            Execution by: ManTech Design and Development Corporation

     To record the adoption of the Plan, ManTech Design and Development
Corporation has caused it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/  JOHN A. MOORE, JR.
                                                 -----------------------

<PAGE>

                                   APPENDIX B

           Execution by: ManTech Advanced Systems International, Inc.

     To record the adoption of the Plan, ManTech Advanced Systems International,
Inc. has caused it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/  JOHN A. MOORE, JR.
                                                 -----------------------

<PAGE>

                                   APPENDIX B

       Execution by: ManTech Telecommunications & Information Systems Co.

     To record the adoption of the Plan, ManTech Telecommunications &
Information Systems Co. has caused it to be executed on this 4/th/ day of
January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/  JOHN A. MOORE, JR.
                                                 -----------------------

<PAGE>

                                   APPENDIX B

                Execution by: ManTech Germany Systems Corporation

     To record the adoption of the Plan, ManTech Germany Systems Corporation has
caused it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/ JOHN A. MOORE, JR.
                                                 ----------------------

<PAGE>

                                   APPENDIX B

                 Execution by: ManTech China Systems Corporation

     To record the adoption of the Plan, ManTech China Systems Corporation has
caused it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/ JOHN A. MOORE, JR.
                                                 ----------------------

<PAGE>

                                   APPENDIX B

                    Execution by: ManTech Y2K Solutions, Inc.

     To record the adoption of the Plan, ManTech Y2K Solutions, Inc. has caused
it to be executed on this 4/th/ day of January, 1999.


                                             PARTICIPATING EMPLOYER:

                                             By: /s/  JOHN A. MOORE, JR.
                                                 -----------------------