This is a sole-source contract modification for Lockheed Martin to complete planning and design activities for integrating the Joint Strike Missile onto specific F-35A aircraft. The work is intended for Partner and Foreign Military Sales countries. The notice explicitly states it is not a request for competitive proposals, though capability statements may be considered if received within 15 days of the synopsis publication. Subcontracting opportunities may be available directly through Lockheed Martin. The data involved is export-controlled and not available to foreign sources.