The Bow Street Runners were the law enforcement officers of the Bow Street Magistrates' Court in the City of Westminster. They have been called London's first professional police force. The force originally numbered six men and was founded in 1749 by magistrate Henry Fielding, who was also well known as an author. His assistant, brother, and successor as magistrate, John Fielding, moulded the constables into a professional and effective force. Bow Street Runners was the public's nickname for the officers although the officers did not use the term themselves and considered it derogatory. The group was disbanded in 1839 and its personnel merged with the Metropolitan Police, which had been formed ten years earlier.

Law enforcement is the activity of some members of government who act in an organized manner to enforce the law by discovering, investigating, deterring, rehabilitating, or punishing people who violate the rules and norms governing that society. The term encompasses police, courts, and corrections. These three components of the criminal Justice system may operate independently of each other or collectively through the use of record sharing and cooperation. Throughout the world, law enforcement are also associated with protecting the public, life, property, and keeping the peace in society.