In New York City, a borough is a unique form of government which administers the five fundamental constituent parts that make up the consolidated city; it differs significantly from other borough forms of government used in other parts of the Tri-State Region and elsewhere in the United States.

New York City is often referred to collectively as The Five Boroughs; this phrase is used to refer to New York City as a whole unambiguously, avoiding confusion with any particular borough or with the greater metropolitan area. It is often used by politicians to counter a focus on Manhattan and to place all five boroughs on an equal standing.

Unlike most American cities, which lie within a single county, or, at most, constitute a county in themselves, each of New York City's five boroughs is coextensive with a county of New York state:

• The Borough of The Bronx is Bronx County.
• The Borough of Brooklyn is Kings County.
• The Borough of Manhattan is New York County.
• The Borough of Queens is Queens County.
• The Borough of Staten Island is Richmond County.

All boroughs were created in 1898 during consolidation, when the city's current boundaries were established. The Borough of the Bronx was originally those parts of New York County that had been previously ceded by Westchester County, until Bronx County was created in 1914. The Borough of Queens originally consisted of the western part of Queens County, until Nassau County was created out of the three eastern towns in 1899. The Borough of Staten Island was officially the Borough of Richmond until the name was changed in 1975 to reflect its common appellation.

Each borough is represented by a Borough President and has, with the exception of Manhattan, a borough hall (the same functions, and others, reside in the Manhattan Municipal Building). Since the abolishment of the Board of Estimate in 1990 (due to a 1989 ruling of the U.S. Supreme Court) the Borough President now has minimal executive powers, and there is no legislative function within a borough. Most executive power is exercised by the Mayor of New York, and legislative functions are the responsibility of the members of the New York City Council. Because they are counties, each borough also elects a District Attorney, as does every other county of the state. Some Civil Court judges are also elected on a borough-wide basis, although they are generally eligible to serve throughout the city.