10 U.S.C. § 3101

In this chapter: (1) The term “best value” means, with respect to an acquisition, the optimal combination of cost, quality, technical capability or solution quality, and delivery schedule. (2) The term “capability requirement” means a capability that is critical or essential to address an operational problem. (3) The term “cost-effective” means, with respect to an acquisition, delivering superior end-user results at equal or lower cost compared to alternatives. (4) The term “operational problem” means— (A) a challenge of a military department in achieving an assigned military objective based on current doctrine, emerging threats, or future concepts; and (B) may include limitations in capabilities, capacity, resources, or the ability to effectively and efficiently coordinate across the joint force, with another combatant command, or among military capabilities. (5) The term “service chief” means— (A) the Chief of Staff of the Army, with respect to matters concerning the Army; (B) the Chief of Naval Operations, with respect to matters concerning the Navy; (C) the Commandant of the Marine Corps, with respect to matters concerning the Marine Corps; (D) the Chief of Staff of the Air Force, with respect to matters concerning the Air Force; and (E) the Chief of Space Operations, with respect to matters concerning the Space Force.