The New Ireland Forum was a forum in 1983–84 at which Irish nationalist political parties discussed potential political developments that might alleviate the Troubles in Northern Ireland. The Forum was established by Garret FitzGerald, then Taoiseach, under the influence of John Hume, for "consultations on the manner in which lasting peace and stability can be achieved in a new Ireland through the democratic process". The Forum was initially dismissed, by Unionists, Sinn Féin, and others, as a nationalist talking-shop. The Forum's report, published on 2 May 1984, listed three possible alternative structures: a unitary state, a federal/confederal state, and joint British/Irish authority. The British Prime Minister, Margaret Thatcher, dismissed the three alternatives one by one at a press conference, each time saying, "that is out", in a response that became known as the "out, out, out" speech. However, Garret Fitzgerald, who described the Forum's report as "an agenda not a blueprint", valued it as establishing a nationalist consensus from which the 1985 Anglo-Irish Agreement could be framed.
In the aftermath of the 1981 hunger strikes, "physical force Irish republicanism" represented by Provisional Sinn Féin was gaining support in Northern Ireland at the expense of the "constitutional nationalism" represented by the Social Democratic and Labour Party (SDLP). Garret FitzGerald became Taoiseach after the Republic's 1981 general election and announced a "constitutional crusade", including a reframing of the state's attitude to Northern Ireland. He lost power quickly but regained it in the November 1982 election. Before the previous month's election to the reconstituted Northern Ireland Assembly, John Hume had proposed a "Council for a New Ireland" in the SDLP manifesto. Fitzgerald persuaded Hume to accept a Forum open to non-nationalist parties, though in the event only nationalist parties joined. The SDLP's participation persuaded Fianna Fáil to join. The forum was open to "all democratic parties which reject violence and which have members elected or appointed to either House of the Oireachtas or the Northern Ireland Assembly". From the Assembly, only the SDLP participated; Sinn Féin were excluded, and the Alliance Party and Unionist parties stayed away. From the Oireachtas, the three main parties —Fianna Fáil, Fine Gael, the Labour Party— joined. Independent TDs and Senators were not eligible for membership. The SDLP was abstentionist in the Unionist-dominated Northern Ireland Assembly, which meant its representatives were able to devote more time to the Forum.