ManTech Receives 2004 NASA Goddard Space Flight Center Contractor Excellence Award.

FAIRFAX, Va. -- Company is a long-time NASA contractor and a leading provider of IT and engineering solutions for the military and civil space community

ManTech International Corporation (Nasdaq:MANT), a leading provider of innovative technologies and solutions focused on mission-critical national security programs announced today that it has received the NASA Goddard Space Flight Center (GSFC) 2004 Contractor Excellence Award. The annual award, which was presented earlier this month, is given to the contractor who makes a substantial contribution to the mission of the GSFC and is dedicated to a philosophy of continuous improvement. The award winners are chosen by NASA after a rigorous process and automatically become eligible for the George M. Low Award, NASA's highest quality award for contractors.

ManTech International Corporation has been supporting the NASA GFSC for more than 30 years as the principal contractor responsible for comprehensive integration, environmental test engineering, and operations support for systems such as the Hubble Space Telescope. The company has a tradition of providing superior support to NASA. In 2002, ManTech received the NASA George M. Low Award as the premier large business services contractor, and in 2000 ManTech received the Goddard Contractor Excellence Award.

"The dedication and commitment of the ManTech team at NASA Goddard, led by Mike Yachmetz, Vice President, ManTech Space Systems, has been outstanding," said George J. Pedersen, Chairman of the Board and CEO, ManTech International Corporation. "Their support to the mission and level of technical competency is excellent and what's most impressive is that each year, they continue to improve," said Mr. Pedersen.

In order to receive the GSFC Contractor Excellence Award, which has been awarded annually since 1988, applicants must achieve measurable results over a three-year period based on customer satisfaction; technical and schedule performance; cost; leadership and continuous improvement; and innovative management and technology breakthroughs.

"Our ManTech personnel are thoroughly integrated with the NASA Goddard Team. It is a wonderful example of the best of American government, industry and union cooperation and respect," said Jay W. Kelley, President, ManTech Space Systems.

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 and the Departments of Defense, State, Homeland Security, Justice, NASA 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 is helping the Department of Justice's U.S. Marshals Service deploy a common, office automation system. With annual revenues of $842 million for 2004 and more than 5,400 highly qualified employees and several thousand consultants, the company operates in the United States and 40 countries worldwide. In 2004, ManTech was selected by Business Week magazine as one of the Top 100 Hot Growth Companies and ranked by VARBusiness magazine as one of its Top 50 Fastest-Growing Solution Providers. 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 those anticipated results. For a discussion of such risks and uncertainties, please refer to the section titled "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 16, 2005, 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.