Shawn O'Brien Named Senior Vice President of Program/Business Develop

    Business Editors/High-Tech Editors

    FAIRFAX, Va.--(BUSINESS WIRE)--Feb. 16, 2005--ManTech International Corporation (Nasdaq:MANT), a leading provider of innovative technologies and solutions focused on mission-critical national security programs for the Department of Defense, Intelligence Community, the Department of State, the Department of Justice, Department of Homeland Security, and other federal government customers announced today that Shawn R. O'Brien has been named Senior Vice President of Program/Business Development.
    Robert A. Coleman, President and Chief Operating Officer, ManTech International Corporation said, "As we continue to sharpen our business focus on the Intelligence Community and Department of Defense, Shawn's experience in this area will prove invaluable. ManTech is currently providing some very sophisticated and successful advanced technology solutions and services to many different organizations throughout DOD and the Intelligence Community. Under Shawn's leadership we will continue to broaden the availability of these capabilities to new customers, develop new offerings, and pull-together existing services to offer complete solutions to our customer's challenges."
    Shawn has a strong background in business development with DOD and the Intelligence Communities, including significant experience in intelligence policy, collection, production and system planning. He also served 20 years in the United States Air Force.
    Prior to joining ManTech, Shawn served in various strategic business development positions at Northrop Grumman/TASC, including directing their Space and Intelligence Operating Unit, Business Development organization. During his Air Force career, Shawn had a variety of leadership roles such as the Director of Space Policy, NRO; Chief of the Collection Systems Branch, Strategic Air Command; and Deputy Executive Officer, Deputy Chief of Staff for Intelligence, Strategic Air Command.
    Shawn has a master's in education/human resource management from Boston University and a bachelor's degree in occupational education from Southern Illinois University.

    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 Department of Defense, the Intelligence Community, the Department of State, the Department of Justice, the Department of Homeland Security and other U.S. federal government customers. ManTech's expertise includes 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. Marshall Service deploy a common, office automation system. With projected annual revenues in excess of $800 million for 2004 and more than 5,500 highly qualified employees and several thousand consultants, the company operates in the United States and more than 30 countries worldwide. In 2004, ManTech was selected by Business Week magazine as one of the Top 100 Hot Growth Companies and was ranked as one of the Top 50 Fastest-Growing Solution Providers by VARBusiness magazine. 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, could be interpreted to be "forward-looking" statements that ManTech believes to be within the definition in the Private Securities Litigation Reform Act of 1995. Such statements are subject to factors that could cause actual results to differ materially from 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 15, 2004, and, from time to time, in ManTech's other filings with the Securities and Exchange Commission, including, among others, its reports on Form 8-K and Form 10-Q. The forward-looking statements included in this press release are only made as of the date of this press release, and the Company undertakes no obligation to update any of the forward- looking statements made herein, whether as a result of new information, future events, changes in expectations or otherwise.

--30--TG/ph*

CONTACT: ManTech International Corporation, Fairfax Mark Root, 703-218-8397 Cell: 703-407-9393 mark.root@mantech.com or Maureen Crystal, 703-218-8262 maureen.crystal@mantech.com

KEYWORD: VIRGINIA DISTRICT OF COLUMBIA INDUSTRY KEYWORD: HARDWARE AEROSPACE/DEFENSE GOVERNMENT SOFTWARE NETWORKING MANAGEMENT CHANGES SOURCE: ManTech International Corporation

Copyright Business Wire 2005