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UNITED STATES
SECURITIES AND EXCHANGE COMMISSIONWASHINGTON, D.C. 20549

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FORM 10-K/A

ANNUAL REPORT PURSUANT TO SECTION 13 OR 15 (d) OF THE
SECURITIES EXCHANGE ACT OF 1934

(Mark One)

|ý                                           | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934     
|------------------------------------------- | -----------------------------------------------------------------------------------------
|For the fiscal year ended December 31, 2002
|OR                                         
|o                                           | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE- ACT OF 1934

Commission File No. 000-30271

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PEC SOLUTIONS, INC.(Exact name of registrant as specified in its charter)

|Delaware(State or other jurisdiction of
incorporation or organization) |  | 54-1339972(IRS Employer Identification No.)
|---------------------------------------------------------------------- |  | -------------------------------------------

12730 Fair Lakes Circle, Fairfax, Virginia 22033(Address of principal executive offices, zip code)

Registrant's telephone number, including area code: (703) 679-4900

Securities registered pursuant to Section 12(b) of the Act: None

Securities registered pursuant to Section 12(g) of the Act:

Common Stock, $0.01 par value(Title of Each Class)

Indicate
by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the
preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past
90 days. Yes ý    No o

Indicate
by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of
registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. ý

Indicate
by check mark whether the registrant is an accelerated filer (as defined in Rule 12b-2 of the Exchange
Act). Yes ý    No o

Aggregate
market value of the voting stock held by non-affiliates of the registrant as of March 28, 2003 was: $145,869,433 based on the closing sale price on the
Nasdaq National Market on that date.

Number
of shares of Common Stock outstanding as of March 28, 2003 was: 27,030,780 shares.

Documents Incorporated By Reference:

Part IIIProxy Statement for the 2003 Annual Meeting of Stockholders on May 21, 2003. Such proxy statement will be filed with the
Securities and Exchange Commission not later than 120 days after the Registrant's fiscal year ended December 31, 2002.

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This form 10K/A is being filed for the sole purpose of filing the signatures to the certifications of the Chief Executive Officer and the Principal Financial and Accounting Officer
pursuant to Section 302 of the Sarbanes-Oxley Act. In addition, it includes the signature on the Auditors Consent Form Exhibit 23.1. The signatures were inadvertently omitted from the Company's
10K previously filed with the Securities and Exchange Commission on March 28, 2003.

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Certifications

I, David C. Karlgaard, certify that:





|March 28, 2003 |  | By: |  | /s/DAVID C. KARLGAARDName: David C. Karlgaard
Title: President, Chief Executive Officer and Chairman (Principal Executive Officer)
|-------------- |  | --- |  | ----------------------------------------------------------------------------------------------------------------------------------

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I, Stuart R. Lloyd, certify that:





|March 28, 2003 |  | By: |  | /s/STUART R. LLOYDName: Stuart R. Lloyd
Title: Chief Financial Officer, Senior Vice President and Director (Principal Financial and Accounting Officer)
|-------------- |  | --- |  | -------------------------------------------------------------------------------------------------------------------------------------------------------

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