Leidos, formerly known as Science Applications International Corporation, is an American defense, aviation, information technology, and biomedical research company headquartered in Reston, Virginia, that provides scientific, engineering, systems integration, and technical services. Leidos merged with Lockheed Martin’s IT sector in August 2016 for Information Systems & Global Solutions business to create the defense industry’s largest IT services provider. The Leidos-Lockheed Martin merger is one of the biggest transactions thus far in the consolidation of a defense sector. Leidos works extensively with the United States Department of Defense, the United States Department of Homeland Security, and the United States Intelligence Community, including the NSA, as well as other U.S. government civil agencies and selected commercial markets.