8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): July 19, 2010

ManTech International Corporation

(Exact name of registrant as specified in its charter)

Delaware	000-49604	22-1852179
(State or other jurisdiction of incorporation)	(Commission File Number)	(IRS Employer Identification No.)

12015 Lee Jackson Highway, Fairfax, VA	22033
(Address of principal executive offices)	(Zip Code)

Registrant’s telephone number, including area code: (703) 218-6000

(Former name or former address, if changed since last report.)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2.):

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

(b) On July 19, 2010, Mr. Lawrence B. Prior, III, informed the Company of his decision to resign from his position as President and Chief Operating Officer of ManTech International Corporation and to resign from his position on the Company’s Board of Directors.

(c) Pending a decision on a potential successor by the Board of Directors, Mr. George Pedersen, the Company’s Chairman of the Board and Chief Executive Officer, will perform the functions of the Company’s President on an interim basis.

A copy of a press release, dated July 19, 2010, announcing Mr. Prior’s resignation is furnished as Exhibit 99.1 to this Current Report on Form 8-K.

Item 9.01 Financial Statements and Exhibits

(d) Exhibits

Exhibit No.	Description of Exhibit
99.1	ManTech International Corporation Press Release, dated July 19, 2010, announcing the resignation of Lawrence B. Prior, III as President and Chief Operating Officer of the Company and as a Director.

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 hereunto duly authorized.

	ManTech International Corporation
Date: July 20, 2010	By:	/S/    MICHAEL R. PUTNAM
		Michael R. Putnam
		SVP – Corporate & Regulatory Affairs

EX-99.1

Exhibit 99.1

Media Relations: Amy Gooen VP, Organizational Communications (703) 218-6387 amy.gooen@mantech.com Investor Relations: Stuart Davis EVP, Strategy and Communications (703) 218-8269 stuart.davis@mantech.com

ManTech Announces a Senior Management Change

FAIRFAX, Va., July 19, 2010—ManTech International Corporation (NASDAQ: MANT), a leading provider of innovative technologies and solutions for mission-critical national security programs, today announced that Lawrence B. Prior III has submitted, and ManTech has accepted, his resignation as president and chief operating officer. Pending a decision on a successor, ManTech International Chairman and Chief Executive Officer George J. Pedersen will assume the responsibilities of president of ManTech, and the three current Operating Group Presidents will assume the Chief Operating Officer duties for their respective operations.

“We have an energetic and experienced leadership team that will continue to focus on top-line growth, profitability and additional corporate acquisitions that complement ManTech’s strategy. ManTech completed its last corporate acquisition in January, when it acquired Sensor Technologies Inc.,” said Pedersen. “The ManTech team will continue its excellent talent management and program execution around the world, where our 9,000 employees support the nation’s critical missions.”

“ManTech is poised to continue its market-leading growth, and we are absolutely committed to being the best company in our industry by all measures. We believe our solid financial position will continue to be a catalyst for our success. We thank Larry for his contributions over the past year and wish him well in his future endeavors,” Pedersen added.

About ManTech International Corporation

Headquartered in Fairfax, Va., with approximately 9,000 professionals, ManTech is a leading provider of innovative technologies and solutions for mission-critical national security programs for the intelligence community; the departments of Defense, State, Homeland Security and Justice; the space community; the National Oceanic and Atmospheric Administration; and other U.S. federal government customers. ManTech’s expertise includes systems engineering, systems integration, enterprise architecture, cyber security, information assurance, intelligence operations and analysis support, network and critical infrastructure protection, information operations and information warfare support, information technology, communications integration, global logistics and supply chain management, and service-oriented architectures. Additional information on ManTech can be found at www.mantech.com.

Forward-Looking Information

Statements in this announcement, other than historical data and information, constitute forward-looking statements that involve risks and uncertainties. A number of factors could cause our actual results, performance, achievements or industry results to be very different from the results, performance or achievements expressed or implied by such forward-looking statements. Some of these factors include, but are not limited to, the risk factors set forth in ManTech’s Annual Report on Form 10-K for the period ended December 31, 2009, and other such filings that ManTech makes with the U.S. Securities and Exchange Commission (SEC) from time to time. Due to such uncertainties and risks, readers are cautioned not to place undue reliance on such forward-looking statements, which speak only as of the date hereof.

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