ManTech to Provide IT and Infrastructure Solutions Under the $4 Billion, Army IMOD Program; ManTech will support the Lucent Technologies and Engineering and Professional Services teams.

FAIRFAX, Va. -- ManTech International Corporation (Nasdaq:MANT), a leading provider of innovative technologies and solutions focused on mission-critical national security programs for the Intelligence Community; the Departments of Defense, State, Homeland Security, and Justice; the Space Community; and other U.S. federal government customers, announced today that it is a subcontractor on the $4 billion, U.S. Army Infrastructure Modernization (IMOD) program. ManTech will support Lucent Technologies and Engineering and Professional Services Inc. under the multiple-award program that provides information technology and telecommunications services.

IMOD is a 10-year, performance-based, indefinite-delivery, indefinite-quantity contract managed by the Army Project Manager, Defense Communications and Army Switched Systems. The IMOD contracts will replace the Digital Switched Systems Modernization Program (DSSMP) contracts that expire in June 2007. DSSMP supplies telecommunications and support to government and military agencies around the world, including switching and networking technologies, installation, and support services and logistics.

IMOD will modernize the fiber-optic cable and wireless communications at Army bases and installations around the world in order to integrate voice, data, cable plant and/or transmission products and services into a single, integrated communications system.

ManTech also announced in April that it is a subcontractor on the U.S. Army Information Technology Enterprise Solutions - Services (ITES-2S) program, a multi-award, nine-year, $20 billion contract to provide the Army and other federal agencies with IT services, products, and solutions.

"ManTech has recently been awarded a number of important contracts - such as IMOD and ITES-2S - that support the increased demands and expanded role of our military at home and abroad," said Eugene C. Renzi, ManTech Senior Executive Vice President, and President of the ManTech Defense Systems Group. "These contracts create the foundation for DOD's new transformation requirements and provide continuity of operation, infrastructure connectivity and operational support for the expanded mission, daily sustainment and counter-insurgency activities taking place around the globe. As a leading provider of total sustainment solutions and services including integrated logistics; systems engineering; test and evaluation; and Command, Control, Communications, Computers, Intelligence (C4I) infrastructure design, installation and maintenance - we are prominently positioned to support these emerging requirements."

About ManTech International Corporation:

Headquartered in Fairfax, Virginia, ManTech International Corporation 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; and other U.S. federal government customers. ManTech's expertise includes systems engineering, systems integration, technology and software development, enterprise security architecture, information assurance, intelligence operations support, network and critical infrastructure protection, information technology, communications integration and engineering support. The company supports the advanced telecommunications systems that are used in Operation Iraqi Freedom and in other parts of the world; provides the physical and cyber security to protect U.S. embassies all over the world; has developed a secure, collaborative communications system for the U.S. Department of Homeland Security; and builds and maintains secure databases that track terrorists. With over 6,000 highly qualified employees, the company operates in the United States and over 44 countries worldwide. In 2005, Red Herring magazine selected ManTech as one of its Small Cap 100 Companies. Additional information on ManTech can be found at www.mantech.com.

Forward-Looking Information:

Statements and assumptions made in this press release, which do not address historical facts, constitute "forward-looking" statements that ManTech believes to be within the definition in the Private Securities Litigation Reform Act of 1995 and involve risks and uncertainties, many of which are outside of our control. Such forward-looking statements are subject to factors that could cause actual results to differ materially from anticipated results. The factors that could cause actual results to differ materially from those indicated by such forward-looking statements include but are not limited to: the failure of the government to award task orders to ManTech, allot funds to complete performance of the task orders awarded to ManTech, or exercise contract options; the risk of contract performance; government contract procurement (such as bid protest) and termination risks; competitive factors such as pricing pressures and/or competition to hire and retain employees; and material changes in laws or regulations applicable to the Company's businesses. For a discussion of these and other risks and uncertainties, please refer to the section entitled "Risks Related to the Company's Business" in ManTech's Annual Report on Form 10-K filed with the Securities and Exchange Commission on March 10, 2006, and, from time to time, in ManTech's other filings with the Securities and Exchange Commission, including among others, its reports on Form 10-Q and Form 8-K. The forward-looking statements included in this news release are only made as of the date of this news release and ManTech undertakes no obligation to publicly update any of the forward-looking statements made herein, whether as a result of new information, subsequent events or circumstances, changes in expectations or otherwise.