Scotland Yard is a metonym for the headquarters of the Metropolitan Police Service, and the Police Community Support Officers, the territorial police force responsible for policing all 32 boroughs of London, excluding the City of London.
The name derives from the location of the original Metropolitan Police headquarters at 4 Whitehall Place, which had a rear entrance on a street called Great Scotland Yard. The Scotland Yard entrance became the public entrance to the police station, and over time the street and the Metropolitan Police became synonymous. The New York Times wrote in 1964 that just as Wall Street gave its name to New York's financial district, Scotland Yard became the name for police activity in London.