10-Q/A

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q/A

Amendment No. 1

(Mark One)

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

For the quarterly period ended March 31, 2005

or

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

For the transition period from              to             

Commission File No. 000-49604

ManTech International Corporation

(Exact name of registrant as specified in its charter)

Delaware	22-1852179
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
12015 Lee Jackson Highway, Fairfax, VA	22033
(Address of principal executive offices)	(Zip Code)

(703) 218-6000

(Registrant’s telephone number, including area code)

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.    x  Yes    ¨  No

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

As of May 3, 2005, there were issued and outstanding 17,590,454 shares of our Class A Common Stock and 15,065,293 shares of our Class B Common Stock.

Explanatory Note

On May 9, 2005, ManTech International Corporation (the “Company”) filed its Quarterly Report on Form 10-Q for its quarter ended March 31, 2005 (the “Form 10-Q”). The Company is filing this Amendment No. 1 to our Form 10-Q solely to include the additional certification of the Chief Financial Officer to include in paragraph 4 certain statements regarding internal controls over financial reporting that were inadvertently omitted from the certification previously filed.

Rule 12b-15 under the Exchange Act provides that any amendment to a report required to be accompanied by the certifications specified in Rule 13(a)-14(b) or 15d-14(b) must be accompanied by new certifications of the principal executive officer and principal financial officer. These certifications, which are unchanged from the certifications as originally filed with the Form 10-Q, are therefore also included as Exhibit 32.1.

This Amendment No. 1 does not reflect events occurring after the filing of the Form 10-Q, and, other than the filing of the aforementioned certification, does not modify or update the disclosure in the original Form 10-Q in any way.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

	MANTECH INTERNATIONAL CORPORATION
Date: August 19, 2005	By:	/s/ RONALD R. SPOEHEL
	Name:	Ronald R. Spoehel
	Title:	Executive Vice President, Chief Financial Officer and Director

2

EX-31.1

EXHIBIT 31.3

CERTIFICATION

I, George J. Pedersen, certify that:

1. I have reviewed this quarterly report on Form 10-Q of ManTech International Corporation;

2. Based on my knowledge, this quarterly report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c. Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d. Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of registrant’s board of directors (or persons performing the equivalent function):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: August 19, 2005

By:	/s/ GEORGE J. PEDERSEN
Name:	George J. Pedersen
Title:	Chairman of the Board of Directors and Chief Executive Officer

EX-31.2

EXHIBIT 31.4

CERTIFICATION

I, Ronald R. Spoehel, certify that:

1. I have reviewed this quarterly report on Form 10-Q of ManTech International Corporation;

2. Based on my knowledge, this quarterly report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a. Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b. Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c. Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d. Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of registrant’s board of directors (or persons performing the equivalent function):

a. All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b. Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: August 19, 2005

By:	/s/ RONALD R. SPOEHEL
Name:	Ronald R. Spoehel
Title:	Executive Vice President, Chief Financial Officer and Director

EX-32

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 March 31, 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