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                                                                    EXHIBIT 4.1


      COMMON STOCK                                        COMMON STOCK
         NUMBER                  [PEC LOGO]                  SHARES


INCORPORATED UNDER THE LAWS                                 SEE REVERSE FOR
 OF THE STATE OF DELAWARE                                 CERTAIN DEFINITIONS


                             PEC SOLUTIONS, INC.

                                               CUSIP __________
THIS CERTIFIES THAT


IS THE OWNER OF


   FULLY PAID AND NON-ASSESSABLE SHARES OF COMMON STOCK, $.01 PAR VALUE, OF

                           PEC SOLUTIONS, INC.


(hereinafter called the Corporation), transferable on the books of the
Corporation by the holder hereof in person or by duly authorized attorney
upon surrender of this Certificate properly endorsed.

        This certificate is not valid until countersigned and registered by
the Transfer Agent and registered by the Registrar.

        Witness the facsimile seal of the Corporation and the facsimile
signatures of its duly authorized officers.

Dated:

                           PEC SOLUTIONS, INC.
                                DELAWARE
                              [1999 SEAL]

   /s/ David C. Karlgaard                       /s/ Paul G. Rice
   Chief Executive Officer, President and           Chief Operating Officer and
   Chairman of the Board of Directors               Director


COUNTERSIGNED AND REGISTERED:

American Stock Transfer & Trust Company         /s/ Alan H. Harbitter
TRANSFER AGENT                                      Chief Technology Officer,
AND REGISTRAR                                       Director and Secretary

AUTHORIZED SIGNATURES


                           PEC SOLUTIONS, INC.



        The following abbreviations, when used in the inscription on the face
of this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

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TEN COM-  as tenants in common                    UNIF GIFT MIN ACT-

                                          ______________Custodian______________
TEN ENT-  as tenants by the entireties      (Cust)                 (Minor)
 JT TEN-  as joint tenants with
          right of survivorship and          under Uniform Gifts to Minors Act
          not as tenants in common



          ----------------------------------
                       (State)


    Additional abbreviations may also be used though not in the above list.


        For Value received, _________________________________hereby sell, assign
and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
    IDENTIFYING NUMBER OF ASSIGNEE
------------------------------------

--------------------------------------------------------------------------------


________________________________________________________________________________
  PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE

________________________________________________________________________________

__________________________________________________________________________Shares

of the Common Stock represented by the within Certificate, and do hereby
irrevocably constitute and appoint __________________________________Attorney to
transfer the said stock on the books of the within-named Corporation with full
power of substitution in the premises.

Dated,________________________ X________________________________________________

                               X________________________________________________
                               NOTICE: THE SIGNATURE(S) TO THIS ASSIGNMENT MUST
                               CORRESPOND WITH THE NAME(S) AS WRITTEN UPON THE
                               FACE OF THE CERTIFICATE, IN EVERY PARTICULAR,
                               WITHOUT ALTERATION OR ENLARGEMENT, OR ANY CHANGE
                               WHATSOEVER.


SIGNATURE GUARANTEED:___________________________________________________________
                     THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELGIBLE
                     GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND
                     LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN
                     APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT
                     TO S.E.C. RULE 17Ad-15.