The NYPD Transit Bureau is a part of the NYPD that patrols and responds to emergencies within the New York City transit system. Its responsibility includes the New York City Subway network in Manhattan, the Bronx, Brooklyn, and Queens. However, there are certain units that have citywide responsibilities such as the Homeless Outreach Unit and the Vandals Task Force. The Transit Bureau is divided into Transit Borough Commands. These Borough Commands generally follow the boundaries of the City's geographical boroughs, although there are some notable exceptions. Since there are no subways on Staten Island, there are only four Transit Boroughs: Queens, Bronx, Brooklyn, and Manhattan. Each Transit Borough is further divided into Transit Districts.