The student body is the Brigade of Midshipmen, and the naval service often is called "the fleet". The brigade is divided into two regiments of three battalions each. Five companies make up each battalion, making a total of 30 companies. The midshipmen command structure is headed by a first class midshipman know as the Brigade Commander, chosen for outstanding leadership performance. He or she is responsible for much of the brigade's day-to-day activities as well as the professional training of midshipmen. Overseeing all brigade activities is the Commandant of Midshipmen, an active-duty Navy officer of rear admiral's rank or above. Working for the commandant, experienced Navy and Marine Corps officers are assigned as company and battalion officers.