The Missile Defense Agency is announcing the award of a sole-source indefinite-delivery/indefinite-quantity contract to Lockheed Martin Corporation, Sunnyvale, California. The total ceiling award value is $515.4 million. Under this follow-on contract, the contractor will be responsible for development, integration, and testing of any upgrades to the Terminal High Altitude Area Defense (THAAD) system. Task orders issued under this contract will address the continued development, enhancement, and testing of the THAAD components/system. The THAAD element is comprised of the following components: interceptor, THAAD fire control and communication, launcher, peculiar support equipment, and AN/TPY-2 radar integrated into a weapon system. Examples of task orders include, but are not limited to, communications upgrades, obsolescence mitigation, flight and ground testing, and spiral development to further integrate THAAD in the Ballistic Missile Defense System architecture through development of unifying missile defense functions.