ManTech International Corporation Names Sally Sullivan, Executive Vice President, Business Development

Ms. Sullivan joins ManTech from Bechtel National, Inc., where she was the Vice President for Defense, Space & Secured Infrastructure, responsible for growing business with DoD, the Intelligence Community, key federal civil agencies and select foreign governments. This included the design and delivery of complex operational systems and infrastructures as well as specialized services such as government owned/contractor operated facilities, environmental remediation, chemical/nuclear demilitarization and new counterterrorism technologies and interagency response capabilities. Prior to joining Bechtel, she was the Sector Vice President for Business Development of Northrop Grumman Mission Systems, where she had responsibility for the growth and development of the unit’s $6 billion Command, Control, Communications, Computers, Intelligence, Surveillance and Reconnaissance (C4ISR) business and directed its advanced capabilities demonstration lab. Her portfolio spanned missiles, missile defense, and C4ISR, and she was the corporate lead executive for key customers such as the Joint Forces Command, U.S. Northern Command, U.S. Air Force Space Command, U.S. Army Training and Doctrine Command, Missile Defense Agency and NASA.

"It gives me great pleasure to welcome Ms. Sullivan to ManTech. Her extensive customer-focused experience and expertise in our markets and other governmental areas will be critical in helping us achieve our multi-year strategic growth goals," said George J. Pedersen, Chairman of the Board and Chief Executive Officer, ManTech International Corporation. "Ms. Sullivan will be a key member of our executive management team, and we look forward to working with her as we continue to drive our successful performance and make ManTech the premier mid-tier national security firm in the marketplace."

Lawrence B. Prior III, ManTech's President and Chief Operating Officer, said, "Sally is a respected leader in our marketplace and her depth of experience and record of success will help ensure that our business development strategy aligns with our long-term growth plans while remaining focused on our customers’ critical missions. Her enterprise-wide business development approach will magnify our recent wins in DHS and cyber, and she will enhance ManTech’s market differentiators and expand our market presence. We are delighted to have Sally join our team.”

"I am excited to join ManTech’s exceptional management team and help build and align our customer-focused company-wide strategy to continue ManTech's record of 41-plus years of successful growth," said Ms. Sullivan, Executive Vice President, Business Development, ManTech International Corporation. "As I look out over the industry, ManTech is a market leader in cyber Computer Network Operations as well as C4ISR and logistics and is well-positioned to take advantage of changes in our marketplace. ManTech’s customer mission-driven culture and focus on employees and shareholders is a great differentiator, and I see significant market opportunities for growth and ensuring that our customers’ goals are met with every program we support."

Before joining Northrop Grumman, Ms. Sullivan was Executive Director for the Public Sector division of ChoicePoint, Inc. and in three years took the organization from a startup to becoming the preeminent player in the government automated public records market. She began her career at EDS where she held key roles of increasing responsibility over a 17-year period. Ms. Sullivan led the teams that conceived, developed and deployed some of the first-ever healthcare systems used in medical readiness, transport and logistics. She managed and directed an operational staff of several hundred engineers and communications experts responsible for the development and worldwide deployment of these solutions.

Ms. Sullivan earned a Bachelor of Science degree from Texas Tech University in 1980. She serves on the Advisory Board of CharityWorks, a high impact organization that unites corporate leaders and donors in partnership with Washington Metropolitan area non-profit organizations to address the health, education and poverty of children. She is also the Board Chair of The Fishing School, an after-school safe-haven and educational support center for vulnerable children.

About ManTech International Corporation:

Headquartered in Fairfax, Virginia with approximately 8,000 professionals, 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; National Oceanic and Atmospheric Administration; and other U.S. federal government customers. ManTech’s expertise includes systems engineering, systems integration, software development services, 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. The company supports the advanced telecommunications systems that are used in Operation Iraqi Freedom and in other parts of 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. The company operates in the United States and 40 countries. In 2008, BusinessWeek magazine chose ManTech for its ‘InfoTech 100’ listing representing the best performing tech companies in the world; Forbes.com named ManTech as one of the 400 Best Big Companies in the nation; and A-Space, a Web 2.0 enhanced collaboration tool that ManTech developed for the Intelligence Community was named one of the Top 50 Inventions of the Year by Time magazine. Also in 2008, GI Jobs magazine named ManTech a Top Ten Military Friendly Employer for the third year in a row. 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. Words such as "may,” "will,” "intends,” "should,” "expects,” "plans,” "projects,” "anticipates,” "believes,” "estimates,” "predicts,” "potential,” "continue,” or "opportunity," or the negative of these terms or words of similar import are intended to identify forward-looking statements.

These forward-looking statements are subject to known and unknown risks and uncertainties, which could cause actual results to differ materially from those anticipated, including, without limitation: adverse changes in U.S. government spending priorities; failure to retain existing U.S. government contracts, win new contracts, or win recompetes; adverse results of U.S. government audits of our government contracts; risks associated with complex U.S. government procurement laws and regulations; adverse effect of contract consolidations; risk of contract performance or termination; failure to obtain option awards, task orders or funding under contracts; adverse changes in our mix of contract types; failure to successfully integrate recently acquired companies or businesses into our operations or to realize any accretive or synergistic effects from such acquisitions; failure to identify, execute or effectively integrate future acquisitions; risks of financing, such as increases in interest rates and restrictions imposed by our credit agreement; risks related to an inability to obtain new or additional financing; and competition. These and other risk factors are more fully discussed in the section entitled "Risks Factors" in ManTech's Annual Report on Form 10-K filed with the Securities and Exchange Commission on February 27, 2009, 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.

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.

ManTech International Corporation
Mark Root
Executive Director, Corp. Communications
703-218-8397; cell: 571-259-1169
mark.root@mantech.com
or
Stuart Davis
Corporate EVP, Strategy and IR
703-218-8269; cell: 703-677-5248
stuart.davis@mantech.com