Since 1998, Northern Ireland has devolved government within the United Kingdom. The government and Parliament of the United Kingdom are responsible for reserved and excepted matters. Reserved matters are a list of policy areas (such as civil aviation, units of measurement, and human genetics), which the Westminster Parliament may devolve to the Northern Ireland Assembly at some time in future. Excepted matters (such as international relations, taxation and elections) are never expected to be considered for devolution. On all other matters, the Northern Ireland Executive together with the 90-member Northern Ireland Assembly may legislate and govern for Northern Ireland. Additionally, devolution in Northern Ireland is dependent upon participation by members of the Northern Ireland Executive in the North/South Ministerial Council, which co-ordinates areas of co-operation (such as agriculture, education and health) between Northern Ireland and the Republic of Ireland.
Elections to the Northern Ireland Assembly are by single transferable vote with five representatives (Members of the Legislative Assembly, MLAs) elected from 18 parliamentary constituencies. Eighteen representatives to the lower house of the British parliament (Members of Parliament, MPs) are elected from the same constituencies using the first-past-the-post system. However, not all of these take their seats. The seven Sinn Féin MPs refuse to take the required oath to serve Queen Elizabeth II. In addition, the upper house of the UK's parliament, the House of Lords, currently has some 25 appointed members from Northern Ireland. Northern Ireland itself forms a single constituency for elections to the European Union.
The Northern Ireland Office represents the British government in Northern Ireland on reserved matters. The Government of the Republic of Ireland also has the right to "put forward views and proposals" on non-devolved matters in relation to Northern Ireland. The Northern Ireland Office is led by the Secretary of State for Northern Ireland, who sits in the Cabinet of the United Kingdom.
Much of the population of Northern Ireland identifies with one of two different ideologies: unionism (which wants the region to remain part of the United Kingdom) and Irish nationalism (which wants a united Ireland). Unionists are predominantly Ulster Protestant, most of whom belong to the Presbyterian Church in Ireland and the Church of Ireland. Irish nationalists are almost wholly Roman Catholic. There is also a tiny minority of Ulster nationalists (those who want an independent Northern Irish state), whose religious convictions vary.