The Social Democratic and Labour Party (SDLP) is a major nationalist party in Northern Ireland. It was founded in the early 1970s to provide a political movement to unite non-violent nationalists who opposed the campaign of violence of Sinn Féin and its military wing, the Provisional IRA, yet who also wanted to campaign democratically for a united Ireland. Traditionally they have been the main party seeking the reunification of Ireland, but at the 2001 General Election and the 2003 Assembly Election they were outpolled by Sinn Féin, who also won more seats than the SDLP.
It has had three leaders;