Lockheed Martin is an American global aerospace, defense, security, and advanced technology company with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It is headquartered in Bethesda, Maryland, in the Washington Metropolitan Area. Lockheed Martin employs 140,000 people worldwide. Robert J. Stevens is the current Chairman and Chief Executive Officer.

Lockheed Martin is one of the world's largest defense contractors; In 2009, 74% of Lockheed Martin's revenues came from military sales. It received 7.1% of the funds paid out by the Pentagon.

Lockheed Martin operates in four business segments. These comprise, with respective percentages of 2009 total net sales of $45.2 billion, Aeronautics (27%), Electronic Systems (27%), Information Systems & Global Solutions (27%), and Space Systems (19%). In 2009 US Government contracts accounted for $38.4 billion (85%), foreign government contracts $5.8 billion (13%), and commercial and other contracts $0.9 billion (2%). In both 2009 and 2008 the company topped the list of US Federal Contractors.

The company has received the Collier Trophy six times. Most recently (in 2001) for being part of developing the X-35/F-35B LiftFan Propulsion System, and again in 2006 for leading the team that developed the F-22 Raptor fighter jet.