EXHIBIT 32.1
CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER
PURSUANT TO 18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002
In connection with the ManTech International Corporation (the “Company”) Quarterly Report on Form 10-Q for the period ending June 30, 2005 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), we, George J. Pedersen, Chief Executive Officer of the Company, and Ronald R. Spoehel, Chief Financial Officer of the Company, certify pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to the best of our knowledge:
| (1) | The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; and |
| (2) | The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company. |
This certificate is being made for the exclusive purpose of compliance by the Chief Executive Officer and Chief Financial Officer of the Company with the requirements of Section 906 of the Sarbanes-Oxley Act of 2002, and may not be disclosed, distributed or used by any person or for any reason other than as specifically required by law.
Date: August 19, 2005
By: | /s/ GEORGE J. PEDERSEN | |
Name: | George J. Pedersen | |
Title: | Chairman of the Board of Directors and Chief Executive Officer | |
By: | /s/ RONALD R. SPOEHEL | |
Name: | Ronald R. Spoehel | |
Title: | Executive Vice President, Chief Financial Officer and Director | |
