William Donald Massey Sumner (13 August 1913 – 12 May 1990), known as Donald Sumner, was a British Conservative Party politician who later became a judge.
Sumner, the incumbent chairman of the divisional Conservative Association for Orpington, defeated Margaret Thatcher to be adopted prospective candidate for the local constituency.
He remained Member of Parliament for Orpington in Kent until 1962, when he accepted an appointment as a County Court judge.
The resulting Orpington by-election was won by the Liberal Party candidate Eric Lubbock, marking the start of a revival in the fortunes of the Liberals.
This article about a Conservative Member of the Parliament of the United Kingdom representing an English constituency and born in the 1910s is a stub.