United States military seniority
United States military seniority is the method by which the United States Armed Forces determines precedence among commissioned officers. A higher-ranked officer is senior to a lower-ranked one; among officers of the same rank, seniority derives from the date when appointed to that rank. Seniority is used to determine assignments, tactical commands, promotions and general courtesy. To a lesser extent, historical seniority is used to recognize status of honor given to early United States military leaders such as inaugural holders of certain ranks or those officers who served as leaders during major wars and armed conflicts.