The Sergeant Major of the Marine Corps is selected by the Commandant of the Marine Corps to serve as his advisor and as the preeminent and highest ranking enlisted Marine with a protocol equivalency of a three-star general officer. The Sergeant Major of the Marine Corps typically serves a four-year term, though his service is at the discretion of the Commandant of the Marine Corps. 'Sergeant Major of the Marine Corps' is the full wording of the rank, but the verbal address is Sergeant Major.