ManTech to Acquire Worldwide Information Network Systems, Inc.

FAIRFAX, Va.--([ BUSINESS WIRE ])--ManTech International Corporation (Nasdaq: MANT) announced today that it has signed a definitive agreement to acquire Worldwide Information Network Systems, Inc. (WINS) for $90 million in cash. WINS is a leading IT solutions provider, specializing in network and infrastructure engineering, enterprise architecture, cyber security and systems development, software development and integration, and end-user workspace management. ManTech expects the acquisition to be accretive to its earnings per share in 2012.

"This acquisition is consistent with ManTechas long-term strategy to extend our presence in the defense and intelligence markets"

Headquartered in Seabrook, Maryland and founded in 2001, WINS is a privately held company providing global support and IT services to the Department of Defense, Department of State and other agencies. WINS will become a part of ManTechas Mission, Cyber and Technology Solutions group, led by L. William Varner.

The acquisition will enable ManTech to deliver IT services through WINSa prime position on the Defense Intelligence Agencyas (DIA) Solutions for Information Technology Enterprises (SITE) contract, an indefinite delivery/indefinite quantity contract vehicle with a $6.6 billion ceiling and period of performance through 2015.

"This acquisition is consistent with ManTechas long-term strategy to extend our presence in the defense and intelligence markets," said ManTechas Chairman and Chief Executive Officer, George J. Pedersen. aThe addition of WINSa IT capabilities, prime position on the DIA SITE and other contracts will enhance our positioning with important customers and further our growth prospects.a

"We are delighted to join ManTech," said Ulysese Jefferson, president and chief executive officer of WINS. "WINSa unique and innovative IT capabilities will bolster ManTech's significant industry expertise, thus allowing WINS to provide enhanced capability and services to our existing customers. Our core customers need robust IT solutions to overcome tough, complex network challenges. Alongside ManTech, customers will be able to accomplish their missions with more comprehensive offerings of IT solutions.a

The acquisition is subject to various closing conditions and approvals, including approval under the Hart-Scott-Rodino Act, and is expected to be completed in November 2011. The parties will enter into a 338(h)(10) election for tax purposes. ManTech will fund the acquisition from cash on hand.

About ManTech International Corporation

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, Energy, and Justice, including the Federal Bureau of Investigation; the space community; the National Oceanic and Atmospheric Administration; and other U.S. federal government customers. We provide support to critical national security programs for approximately 60 federal agencies through 1,000 current contracts. ManTechas expertise includes command, control, communications, computers, intelligence, surveillance and reconnaissance (C4ISR) lifecycle support, cyber security, global logistics support, intelligence/counter-intelligence support, information technology modernization and sustainment, systems engineering, and test and evaluation. ManTech supports major national missions such as military readiness, terrorist threat detection, information security, and border protection. 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 aforward-lookinga 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 amay,a awill,a aexpect,a aintend,a aanticipate,a abelieve,a aestimate,a or acontinue,a or the negative of these terms or words of similar import are intended to identify forward-looking statements.

These forward-looking statements are inherently subject to risks and uncertainties, and actual results and outcomes may differ materially from the results and outcomes we anticipate. Factors that could cause actual results to differ materially from the results we anticipate, include, but are not limited to, the following: adverse changes in U.S. government spending priorities; failure to retain existing U.S. government contracts, win new contracts or win recompetes; adverse changes in future levels of expenditures for programs we support caused by budgetary pressures facing the federal government; failure to obtain option awards, task orders or funding under contracts; failure to maintain strong relationships with other contractors; adverse changes in our mix of contract types; adverse results of U.S. government audits of our government contracts; risk of contract performance, modification or termination; risks associated with complex U.S. government procurement laws and regulations; risks of financing, such as increases in interest rates and restrictions imposed by our outstanding indebtedness, including the ability to meet financial covenants, and risks related to an inability to obtain new or additional financing; 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; and competition. These and other risk factors are more fully discussed in the section entitled aRisks Factorsa in ManTechas Annual Report on Form 10-K previously filed with the Securities and Exchange Commission on Feb. 25, 2011, Item 1A of Part II of our Quarterly Reports on Form 10-Q, and, from time to time, in ManTechas other filings with the Securities and Exchange Commission.

The forward-looking statements included herein are only made as of the date of this press 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.

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ManTech to Acquire Worldwide Information Network Systems, Inc.