Chief of police is the most common title for the head of a local police department. Alternate titles for a chief of police include police commissioner, colonel, police superintendent, police president or police director. In large urban areas, some departments are led by a civilian overseer, usually referred to as a commissioner. The New York City Police Department is one such case, where the police chief (full title: Chief of department) is the most senior sworn officer. A sheriff is the chief of a county law enforcement agency.