In naval tradition, a mast is a non-judicial punishment ("NJP") disciplinary hearing under which a commanding officer studies and disposes of cases involving those in his command. If the officer conducting the proceeding is either a captain, or a lower ranking officer (typically a commander or lieutenant commander) serving as commanding officer of a naval or coast guard vessel, an aviation squadron, or similar command afloat or ashore, then the proceeding is referred to as a captain's mast. A captain's mast or admiral's mast is a procedure whereby the commanding officer must: