Downing Street was built by Sir George Downing in the 1680s as a speculation. The site had once been part of Whitehall palace. Only three of the original houses remain, on the north side—no. 10 used by the prime minister, no. 11 by the chancellor, and no. 12 by the whips. The south side is taken up by Sir George Gilbert Scott's government offices, built in the 1860s. Behind the modest façade of no. 10 is another large house, fronting the Horse Guards and connected. Sir Robert Walpole accepted it from George II in 1732 for the prime minister of the day. Its nearness to Parliament was an important consideration. The internal arrangements include work by Kent, Taylor, and Soane and are dominated by the staircase, with its collection of engravings and photographs of prime ministers. The cabinet room was redesigned in 1781–3.

J. A. Cannon

Downing Street a street in Westminster, London, between Whitehall and St James's Park. No. 10 (since the time of Sir Robert Walpole) is the official residence of the Prime Minister; No. 11 is the home of the Chancellor of the Exchequer, and the Foreign and Commonwealth Office is also situated in the street. Downing Street is often used to personify the Prime Minister's immediate circle as distinct from the Parliamentary party.
Downing Street Declaration a joint agreement between the British and Irish governments, formulated in 1993, forming the basis of a peace initiative in Northern Ireland.