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                                                                   EXHIBIT 10.12

                                  PEC SOLUTIONS
                          EMPLOYEE STOCK PURCHASE PLAN


         The PEC Solutions Employee Stock Purchase Plan (the "PLAN") provides
eligible employees of PEC Solutions, Inc., a Delaware corporation (the
"COMPANY"), and certain of its subsidiaries with opportunities to purchase
shares of the Company's Common Stock, $0.01 par value per share (the "COMMON
STOCK"). The Plan is intended to benefit the Company by increasing the
employees' interest in the Company's growth and success and encouraging
employees to remain in the employ of the Company or its participating
subsidiaries. The Plan is intended to constitute an "employee stock purchase
plan" within the meaning of section 423 of the Internal Revenue Code of 1986, as
amended (the "CODE"), and shall be so applied and interpreted.

         1. SHARES SUBJECT TO THE PLAN. Subject to adjustment as provided in
Section 13, the aggregate number of shares of Common Stock that may be made
available for purchase under the Plan is 1,000,000 shares. The shares purchased
under the Plan may, in the discretion of the Board of Directors of the Company
(the "BOARD"), be authorized but unissued shares of Common Stock, shares
purchased on the open market, or shares from any other proper source.

         2. ADMINISTRATION. The Plan is administered by the Board or by a
committee appointed by the Board (the "ADMINISTRATOR"). The Administrator has
authority to interpret the Plan, to make, amend and rescind all rules and
regulations for the administration and operation of the Plan, and to make all
other determinations necessary or desirable in administering and operating the
Plan. All actions taken and decisions and determinations made by the
Administrator pursuant to the powers vested in the Administrator under this Plan
shall be in the Administrator's sole and absolute discretion and shall be
conclusive and binding on all parties concerned. No member of the Administrator
shall be liable for any action or determination made in good faith with respect
to the Plan.

         3. ELIGIBILITY. All employees of the Company, including directors who
are employees, and all employees of any subsidiary of the Company (as defined in
Code section 424(f)), now or hereafter existing, that is designated by the
Administrator from time to time as a participating employer under the Plan
("DESIGNATED SUBSIDIARY"), are eligible to participate in the Plan, subject to
such further eligibility requirements as may be specified by the Administrator
consistent with Code section 423.

         4. OPTIONS TO PURCHASE COMMON STOCK.

         (a) Options ("OPTIONS") are granted pursuant to the Plan to each
eligible employee on the first day on which the National Association of
Securities Dealers Automated Quotation ("NASDAQ") system is open for trading
("TRADING DAY") on or after January 1 of each year commencing on or after the
Effective Date (as defined in Section 18), or such other date coincident with or
after the Effective Date as specified by the Administrator. Each Option
terminates on the last Trading Day of a period specified by the Administrator
(each period, an "OPTION PERIOD"). No Option Period may be longer than 27
months. Unless the Administrator determines otherwise, subsequent Option Periods
of equal duration will follow consecutively thereafter, each commencing on the
first Trading Day after the expiration of the preceding Option Period.

         (b) An individual must be employed as an eligible employee by the
Company or a Designated Subsidiary on the first Trading Day of an Option Period
in order to be granted an Option for that Option Period. However, the
Administrator may designate any subsequent Trading Day(s (each


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such designated Trading Day referred to herein as an "INTERIM TRADING DAY") in
an Option Period upon which Options will be granted to eligible employees who
first commence employment with, or first become eligible employees of, the
Company or a Designated Subsidiary after the first Trading Day of the Option
Period. In such event, the Interim Trading Day shall constitute the first
Trading Day of the Option Period for all Options granted on such day for all
purposes under the Plan.

         (c) Each Option represents a right to purchase, on the last Trading Day
of the Option Period or one or more Trading Days within the Option Period
designated by the Administrator (each, including the last Trading Day of the
Option Period, a "PURCHASE DATE"), at the Purchase Price hereinafter provided
for, whole shares of Common Stock up to such maximum number of shares specified
by the Administrator on or before the first day of the Option Period. All
eligible employees granted Options under the Plan for an Option Period shall
have the same rights and privileges with respect to such Options. The purchase
price of each share of Common Stock (the "PURCHASE PRICE") subject to an Option
will be determined by the Administrator, in its discretion, on or before the
beginning of the Option Period; provided, however, that the Purchase Price for
an Option with respect to any Option Period shall never be less than the lesser
of 85 percent of the Fair Market Value of the Common Stock on the (i) first
Trading Day of the Option Period or (ii) the Purchase Date, and shall never be
less than the par value of the Common Stock.

         (d) For purposes of the Plan, "FAIR MARKET VALUE" on a Trading Day
means the average of the high and low sale prices per share of Common Stock as
reflected on the principal consolidated transaction reporting system for
securities listed on any national securities exchange or other market quotation
system on which the Common Stock may be principally listed or quoted or, if
there are no transactions on a Trading Day, then such average for the preceding
Trading Day upon which transactions occurred. However, for the Trading Day that
occurs on the date of the initial public offering of the Common Stock, "Fair
Market Value" shall mean the initial offering price of the Common Stock to the
public as indicated in the Company's final prospectus in connection with such
offering and as such price is negotiated between the Company and the managing
underwriters.

         (e) No employee shall be granted an Option under this Plan if such
employee, immediately after the Option would otherwise be granted, would own 5%
or more of the total combined voting power or value of the stock of the Company
or any subsidiary. For purposes of the preceding sentence, the attribution rules
of Code section 424(d) will apply in determining the stock ownership of an
employee, and all stock which the employee has a contractual right to purchase
will be treated as stock owned by the employee.

         (f) No employee may be granted an Option which permits his rights to
purchase Common Stock under this Plan and all other stock purchase plans of the
Company and its subsidiaries to accrue at a rate which exceeds $25,000 of the
fair market value of such Common Stock (determined at the time such Option is
granted) for each calendar year in which the Option is outstanding at any time,
as required by Code section 423.

         5. PAYROLL DEDUCTIONS AND CASH CONTRIBUTIONS.

         To facilitate payment of the Purchase Price of Options, the
Administrator, in its discretion, may permit eligible employees to authorize
payroll deductions to be made on each payday during the Option Period, and/or to
contribute cash or cash-equivalents to the Company, up to a maximum amount
determined by the Administrator. The Company will maintain bookkeeping accounts
for all employees who authorize payroll deduction or make cash contributions.
Interest will not be paid on any employee



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accounts, unless the Administrator determines otherwise. The Administrator shall
establish rules and procedures, in its discretion, from time to time regarding
elections to authorize payroll deductions, changes in such elections, timing and
manner of cash contributions, and withdrawals from employee accounts. Amounts
credited to employee accounts as of the Purchase Date will be applied to the
payment of the Purchase Price of outstanding Options pursuant to Section 6
below.

         6. EXERCISE OF OPTIONS; PURCHASE OF COMMON STOCK. Options shall be
exercised on the close of business on the Purchase Date. In accordance with
rules established by the Administrator, the Purchase Price of Common Stock
subject to an option shall be paid (i) from funds credited to an eligible
employee's account, (ii) by a broker-assisted cashless exercise in accordance
with Regulation T of the Board of Governors of the Federal Reserve System, or
(iii) by such other method as the Administrator shall determine from time to
time. Options shall be exercised only to the extent the Purchase Price is paid
with respect to whole shares of Common Stock. Any balance remaining in an
employee's account on the Purchase Date after such purchase of Common Stock will
be carried forward automatically into the employee's account for the next
Purchase Date, unless the employee is not an eligible employee with respect to
the next Purchase Date, in which case such amount will be promptly refunded.

         7. ISSUANCE OF CERTIFICATES. As soon as practicable following each
Purchase Date, certificates representing shares of Common Stock purchased under
the Plan will be issued only in the name of the employee, in the name of the
employee and another person of legal age as joint tenants with rights of
survivorship, or (in the Administrator's sole discretion) in the street name of
a brokerage firm, bank or other nominee holder designated by the employee or the
Administrator.

         8. RIGHTS ON RETIREMENT, DEATH, TERMINATION OF EMPLOYMENT, OR
TERMINATION OF STATUS AS ELIGIBLE EMPLOYEE. In the event of an employee's
termination of employment or termination of status as an eligible employee prior
to the Purchase Date (whether as a result of the employee's voluntary or
involuntary termination, retirement, death or otherwise), any outstanding Option
granted to him will immediately terminate, no further payroll deduction will be
taken from any pay due and owing to the employee and the balance in the
employee's account will be paid to the employee or, in the event of the
employee's death, (a) to the executor or administrator of the employee's estate
or (b) if no such executor or administrator has been appointed to the knowledge
of the Administrator, to such other person(s) as the Administrator may, in its
discretion, designate. If, prior to the Purchase Date, the Designated Subsidiary
by which an employee is employed will cease to be a subsidiary of the Company,
or if the employee is transferred to a subsidiary of the Company that is not a
Designated Subsidiary, the employee will be deemed to have terminated employment
for the purposes of this Plan.

         9. OPTIONEES NOT STOCKHOLDERS. Neither the granting of an Option to an
employee nor the deductions from his pay will constitute such employee a
stockholder of the shares of Common Stock covered by an Option under this Plan
until such shares have been purchased by and issued to him.

         10. OPTIONS NOT TRANSFERABLE. Options under this Plan are not
transferable by a participating employee other than by will or the laws of
descent and distribution, and are exercisable during the employee's lifetime
only by the employee.

         11. WITHHOLDING OF TAXES. To the extent that a participating employee
realizes ordinary income in connection with the purchase, sale or other transfer
of any shares of Common Stock purchased under the Plan or the crediting of
interest to the employee's account, the Company may withhold amounts needed to
cover such taxes from any payments otherwise due and owing to the participating
employee or from shares that would otherwise be issued to the participating
employee hereunder. Any participating



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employee who sells or otherwise transfers shares purchased under the Plan must,
within 30 days of such sale or transfer, notify the Company in writing of the
sale or transfer.

         12. APPLICATION OF FUNDS. All funds received or held by the Company
under the Plan may be used for any corporate purpose until applied to the
purchase of Common Stock and/or refunded to participating employees and can be
commingled with other general corporate funds. Participating employees' accounts
will not be segregated.

         13. EFFECT OF CHANGES IN CAPITALIZATION.

         (a) CHANGES IN STOCK. If the number of outstanding shares of Common
Stock is increased or decreased or the shares of Common Stock are changed into
or exchanged for a different number or kind of shares or other securities of the
Company by reason of any recapitalization, reclassification, stock split,
reverse split, combination of shares, exchange of shares, stock dividend, or
other distribution payable in capital stock, or other increase or decrease in
such shares effected without receipt of consideration by the Company occurring
after the Effective Date of the Plan, the number and kind of shares that may be
purchased under the Plan shall be adjusted proportionately and accordingly by
the Company. In addition, the number and kind of shares for which Options are
outstanding shall be similarly adjusted so that the proportionate interest, if
any, of a participating employee immediately following such event shall, to the
extent practicable, be the same as immediately prior to such event. Any such
adjustment in outstanding Options shall not change the aggregate Purchase Price
payable by a participating employee with respect to shares subject to such
Options, but shall include a corresponding proportionate adjustment in the
Purchase Price per share.

         (b) REORGANIZATION IN WHICH THE COMPANY IS THE SURVIVING COMPANY.
Subject to Subsection (c) of this Section 13, if the Company shall be the
surviving corporation in any reorganization, merger or consolidation of the
Company with one or more other corporations, all outstanding Options under the
Plan shall pertain to and apply to the securities to which a holder of the
number of shares of Common Stock subject to such Options would have been
entitled immediately following such reorganization, merger or consolidation,
with a corresponding proportionate adjustment of the Purchase Price per share so
that the aggregate Purchase Price thereafter shall be the same as the aggregate
Purchase Price of the shares subject to such Options immediately prior to such
reorganization, merger or consolidation.

         (c) REORGANIZATION IN WHICH THE COMPANY IS NOT THE SURVIVING COMPANY OR
SALE OF ASSETS OR STOCK. Upon any dissolution or liquidation of the Company, or
upon a merger, consolidation or reorganization of the Company with one or more
other corporations in which the Company is not the surviving corporation, or
upon a sale of all or substantially all of the assets of the Company to another
corporation, or upon any transaction (including, without limitation, a merger or
reorganization in which the Company is the surviving corporation) approved by
the Board that results in any person or entity owning more than 50 percent of
the combined voting power of all classes of stock of the Company, the Plan and
all Options outstanding hereunder shall terminate, except to the extent
provision is made in writing in connection with such transaction for the
continuation of the Plan and/or the assumption of the Options theretofore
granted, or for the substitution for such Options of new Options covering the
stock of a successor corporation, or a parent or subsidiary thereof, with
appropriate adjustments as to the number and kinds of shares and exercise
prices, in which event the Plan and Options theretofore granted shall continue
in the manner and under the terms so provided. In the event of any such
termination of the Plan, the Option Period shall be deemed to have ended on the
last Trading Day prior to such termination, and, unless the Administrator
determines otherwise in its discretion, each participating employee shall have
the


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ability to choose either to (i) have all monies then credited to such employee's
account (including interest, to the extent any has accrued) returned to such
participating employee or (ii) exercise his Options in accordance with Section 6
on such last Trading Day; provided, however, that if a participating employee
does not exercise his right of choice, his Options shall be deemed to have been
automatically exercised in accordance with Section 6 on such last Trading Day.
The Administrator shall send written notice of an event that will result in such
a termination to all participating employees not later than the time at which
the Company gives notice thereof to its stockholders.

         (d) ADJUSTMENTS. Adjustments under this Section 13 related to stock or
securities of the Company shall be made by the Committee, whose determination in
that respect shall be final, binding, and conclusive.

         (e) NO LIMITATIONS ON COMPANY. The grant of an Option pursuant to the
Plan shall not affect or limit in any way the right or power of the Company to
make adjustments, reclassifications, reorganizations or changes of its capital
or business structure or to merge, consolidate, dissolve or liquidate, or to
sell or transfer all or any part of its business or assets.

         14. AMENDMENT OF THE PLAN. The Board may at any time, and from time to
time, amend this Plan in any respect, except that (a) if the approval of any
such amendment by the stockholders of the Company is required by Code section
423, such amendment will not be effected without such approval, and (b) in no
event may any amendment be made which would cause the Plan to fail to comply
with Code section 423 unless expressly so provided by the Board.

         15. INSUFFICIENT SHARES. In the event that the total number of shares
of Common Stock specified in elections to be purchased under any Option plus the
number of shares purchased under all Options previously granted under this Plan
exceeds the maximum number of shares issuable under this Plan, the Administrator
will allot the shares then available on a pro rata basis. Any funds then
remaining in a participating employee's account after purchase of the employee's
pro-rata number of shares will be refunded.

         16. TERMINATION OF THE PLAN. This Plan may be terminated at any time by
the Board. Except as otherwise provided in Section 13(c) hereof, upon
termination of this Plan all outstanding Options shall immediately terminate and
amounts in the employees' accounts will be promptly refunded.

         17. GOVERNMENTAL REGULATIONS.

         (a) The Company's obligation to sell and deliver Common Stock under
this Plan is subject to listing on a national stock exchange or quotation on
Nasdaq and the approval of all governmental authorities required in connection
with the authorization, issuance or sale of such stock.

         (b) The Plan will be governed by the laws of the State of Delaware,
without regard to the conflict of laws principles thereof, except to the extent
that such law is preempted by federal law.

         18. EFFECTIVE DATE. The Plan is effective as of January 1, 2000 (the
"EFFECTIVE DATE"), subject to the approval of the stockholders of the Company
within 12 months of the Effective Date.



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