MANT ManTech International Corporation

ManTech International Corporation (Nasdaq:MANT) will issue its fourth quarter fiscal year 2017 earnings press release after close of market Wednesday, February 21, 2018. Management will discuss financial results in a conference call beginning at 5 p.m. Eastern.

Analysts may participate in the conference call by dialing (877) 638-9567 (domestic) or (253) 237-1032 (international) and entering pass code 1592819. The conference call will be webcast simultaneously to the public through a link on the Investor Relations section of the ManTech website (http://investor.mantech.com). A replay of the conference call will be available on the ManTech website approximately 2 hours after the conclusion of the call.

About ManTech International Corporation

ManTech provides innovative technologies and solutions for mission-critical national security programs for the Intelligence Community; the Departments of Defense, State, Homeland Security, Health and Human Services, Veterans Affairs and Justice, including the Federal Bureau of Investigation (FBI); the space community; and other U.S. government customers. We support important national missions by providing services to approximately 50 federal government agencies under approximately 900 current contracts. ManTech's expertise includes cybersecurity; software and systems development; enterprise information technology; multi-discipline intelligence; program protection and mission assurance; systems engineering; test and evaluation (T&E); command, control, communications, computers, intelligence, surveillance and reconnaissance (C4ISR); training; supply chain management and logistics; and management consulting. Additional information on ManTech can be found at www.mantech.com.

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ManTech International Corporation

Investor Relations Judy Bjornaas Executive Vice President and Chief Financial Officer (703) 218-8269 Investor.Relations@ManTech.com

Media Sue Cushing VP Corporate Communications (703) 814-8369 Sue.Cushing@ManTech.com