Leader of the Opposition

The Leader of the Opposition is a title traditionally held by the leader of the largest opposition party in a Westminster System of parliamentary government. The Leader of the Opposition is invariably seen as the alternative prime minister to the present incumbent, and heads a rival alternative government known as the Shadow Cabinet or Front Bench.

In Commonwealth Realm monarchies, the full title is Leader of Her Majesty's Loyal Opposition.

Leader of the Opposition in the UK

Those who became PM after the end of their session as Leader of the Opposition are indicated in italic.

Sir Henry Campbell-Bannerman (1899-1902)
Arthur Balfour (1902-1911)
Andrew Bonar Law (1911-1915)
none (1915-1922)
Ramsay Macdonald (1922-1924)
\Stanley Baldwin (1924)
Ramsay Macdonald (1924-1929)
Stanley Baldwin (1929-1931)
Arthur Henderson (1931)
George Lansbury (1931-1935)
Clement Attlee (1935-1940)
none (1940-1945)
Winston Churchill (1945-1951)
Clement Attlee (1951-1955)
Hugh Gaitskell (1955-1963)
Harold Wilson (1963-1964)
Edward Heath (1964-1970)
Harold Wilson (1970-1974)
Edward Heath (1974-1975)
Margaret Thatcher (1975-1979)
James Callaghan (1979-1980)
Michael Foot (1980-1983)
Neil Kinnock (1983-1992)
John Smith (1992-1994)
Margaret Beckett (caretaker) (1994)
Tony Blair (1994-1997)
John Major (1997)
William Hague (1997-2001)
Iain Duncan Smith (2001-2003)
Michael Howard (2003-)