10 U.S. Code § 8042 - Headquarters, Marine Corps: general duties
(b) Under the authority, direction, and control of the Secretary of the Navy, the Headquarters, Marine Corps, shall—
subject to subsections (c) and (d) of section 8014 of this title, prepare for such employment of the Marine Corps, and for such recruiting, organizing, supplying, equipping (including research and development), training, servicing, mobilizing, demobilizing, administering, and maintaining of the Marine Corps, as will assist in the execution of any power, duty, or function of the Secretary or the Commandant;
investigate and report upon the efficiency of the Marine Corps and its preparation to support military operations by combatant commanders;
prepare detailed instructions for the execution of approved plans and supervise the execution of those plans and instructions;
as directed by the Secretary or the Commandant, coordinate the action of organizations of the Marine Corps; and
Subsec. (b)(1). Pub. L. 115–232, § 809(a), substituted “section 8014” for “section 5014”.