Coordinates: 51°30′30″N 0°8′44″W / 51.50833°N 0.14556°W
Lansdowne House is a building to the southwest of Berkeley Square in central London, England, much of which is now demolished. It has been owned by three British Prime Ministers and some of its 18th-century interiors, among the best in London, were removed and re-erected elsewhere. The remaining part was granted Grade II* Listed Building status in 1970.
It was designed by Robert Adam as a private house for John Stuart, 3rd Earl of Bute but in 1763 he sold it unfinished to William Petty, 2nd Earl of Shelburne (both men became Prime Minister). Shelburne retained Adam until 1771, when his wife died, with parts of the decoration still incomplete. George Dance the Younger and Robert Smirke later worked on the house.
From 1763 to 1929 it belonged to the Petty-FitzMaurice family, Marquesses of Lansdowne. In 1931 part of the original house was demolished to allow a new road to be built. Since 1935, part of it has been the home of the Lansdowne Club. The positioning of the property was rather unusual. It had a large front garden occupying the whole of the southern side of the square, which it faced side on. This arrangement gave Devonshire House on Piccadilly an open aspect behind as far as the square.