The Social Democratic and Labour Party (SDLP — Irish: Páirtí Sóisialta Daonlathach an Lucht Oibre) is the smaller of the two major nationalist parties in Northern Ireland. The SDLP is also a social democratic party, and is affiliated to the Socialist International. It is a member of the Party of European Socialists. The party's youth wing is SDLP Youth.

The party currently has 3 MPs in the House of Commons, and 18 MLAs in the Northern Ireland Assembly.

Leaders

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• Gerry Fitt (1970-1979)
• John Hume (1979-2001)
• Mark Durkan (2001-present)

Foundation

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The party was founded in the early 1970s. It was formed by former members of the Republican Labour Party - a fragment of the Irish Labour Party, the National Democrats, a small social democratic nationalist party, individual nationalists and members of the Northern Ireland Labour Party. The SDLP initially rejected the Nationalist Party's policy of abstensionism and sought to fight for civil rights within the Stormont system. The SDLP, though, quickly came to the view that Stormont was unreformable and withdrew from the Parliament of Northern Ireland.

Aims

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There is a debate over the intentions of the party's founders, with some now claiming that the aim was to provide a political movement to unite constitutional nationalists who opposed the paramilitary campaign of the Provisional Irish Republican Army and wished to campaign for civil rights for Catholics and a united Ireland by peaceful, constitutional means. However others argue that, as the name implies, the emphasis was originally on creating a social democratic party rather than a nationalist party. This debate between social democracy/socialism and nationalism was to persist for the first decade of the party's existence and still rears its head occasionally. Founder and first leader Gerry Fitt - a former leader of the explicitly socialist Republican Labour Party - would later claim that it was the party's decision to demand a Council of Ireland as part of the Sunningdale Agreement that signified the point at which the party adopted a clear nationalist agenda. He would later leave the party in 1980, claiming that it was no longer the party it was intended to be.

However the party itself argues that its earliest publications show they have remained consistent in their search for a way out of an impasse in Northern Ireland that satisfies nationalist desires and calms unionist fears. The SDLP were the first to advocate the so-called principle of consent - recognising that fundamental changes in Northern Ireland's constitutional status could only come with the agreement of the majority of the people of Northern Ireland, despite the unionist majority partition had guaranteed there. For most of its existence Sinn Féin ridiculed this as a granting of a unionist veto. However, they grudgingly agreed to it, with reservations, when signing up to the Good Friday Agreement, though they contend it should not be a barrier to political progress in other areas. The principle of consent, also widely accepted by moderate unionists, was explicitly endorsed by a large majority of Irish people in referendums (held on the same day) that endorsed the agreement.

Whilst anxious to achieve devolved government in Northern Ireland (which the British Government had prorogued in 1972), the SDLP were also insistent on what was then known as the Irish dimension - in other words a defined constitutional role for the Republic in northern affairs. This issue lead to the downfall of power sharing in 1974 (as the British Government were not prepared to break a general strike objecting to it) and to Gerry Fitt's decision to leave in 1980. Mr Fitt had agreed to enter into talks with Humphrey Atkins, the Secretary of State, which excluded an Irish dimension but was then rebuffed by his party conference.

John Hume was an advocate of a joint authority approach where both the Republic of Ireland and the United Kingdom would exercise political power. This was a central idea of the New Ireland Forum which brought together mainstream Irish parties in the 1980s. However this was rejected out-of-hand by Margaret Thatcher, the Prime Minister, in a speech that became known as "out, out, out" because she dismissed every proposal of the forum by saying "that is out".

The horrified reaction of the Taoiseach Garret FitzGerald to this speech and the electoral success of Sinn Féin following the 1981 Irish Hunger Strike shocked the Thatcher Government and they were receptive to Fitzgerald's lobbying on behalf of the SDLP which eventually led to the Anglo Irish Agreement. However, the agreement was undemocratically forced on the people of Northern Ireland - there was no plebiscite, and this led to opposition from both the unionists and from republicans. Republicans were concerned that the agreement did not go far enough. Unionists staged a peaceful demonstration of some 200,000 people in Belfast city centre, which was duly ignored and not widely reported on national television.

While the SDLP's opponents claimed the party had become "post-nationalist" (following a speech where John Hume referred to "an increasingly post-nationalist Europe") after the Good Friday Agreement, Mark Durkan has recently described the party as republican. Durkan often emphasises to unionists that the protections and constitutional mechanisms of the Good Friday Agreement would remain in place even if Northern Ireland became part of a united Ireland.

Belfast Agreement

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The SDLP were key players in the talks throughout the 1990s that led to the signing of the Belfast Agreement in 1998. John Hume won a Nobel Peace Prize that year with Ulster Unionist Party leader David Trimble in recognition of their efforts.

Power-sharing Government

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The SDLP served in the power-sharing Executive in Northern Ireland, alongside the Ulster Unionist Party, the Democratic Unionist Party and Sinn Féin. (The power-sharing administration is currently in suspension). Both Seamus Mallon and Mark Durkan served as Deputy First Minister alongside the UUP's First Minister David Trimble.

Recent electoral performance

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The SDLP was the largest nationalist party in Northern Ireland from the time of its foundation until the beginning of the 21st century. In 1998, it became the biggest party overall in terms of votes received, the first (as so far, only) time this had been achieved by a nationalist party. In the 2001 General Election and in the 2003 Assembly Election, Sinn Féin won more seats and votes than the SDLP for the first time.

The retirement of John Hume was followed by a period when the party started slipping electorally. In the 2004 European elections Hume stood down and the SDLP failed to retain the seat he had held since 1979, losing to Sinn Féin.