Ireland is a parliamentary, representative democratic republic and a member state of the European Union. While the head of state is the popularly elected President of Ireland, it is a largely ceremonial position, with real political power being vested in the Taoiseach, who is nominated by the Dáil and is the head of the government.

Executive power is exercised by the government, which consists of no more than 15 cabinet ministers, inclusive of the Taoiseach and Tánaiste (the deputy head of government). Legislative power is vested in the Oireachtas, the bicameral national parliament, which consists of Dáil Éireann, Seanad Éireann and the President of Ireland. The judiciary is independent of the executive and the legislature. The head of the judiciary is the Chief Justice, who presides over the Supreme Court.

Ireland has a multi-party system. Fianna Fáil and Fine Gael, historically opposed and competing entities, which both occupy the traditional centre ground, trace their roots to the opposing sides of the Irish Civil War. All governments since 1932 have been led by one or the other party, with Fianna Fáil having had sufficient support at many elections to govern alone. Fluctuations in seat levels allowed changes in governments through different coalitions. From 1932 to 2011, the parties were stable in their support, with Fianna Fáil the largest at each election, Fine Gael the second largest, and on all but two occasions, the Labour Party the third party. The last three elections, however, have each had more volatile results. At the 2011 election, the largest parties in order were Fine Gael, Labour and Fianna Fáil; at the 2016 election, the largest parties in order were Fine Gael, Fianna Fáil and Sinn Féin; and at the 2020 election, the largest parties were Fianna Fáil first in seats (second in votes), Sinn Féin second in seats (first in votes), and then Fine Gael. The result was historically good for Sinn Féin.

In June 2020, leader of Fianna Fáil, Micheál Martin, became the new Taoiseach (head of government). He formed a historic three-party coalition consisting of Fianna Fáil, Fine Gael and the Green Party. It was the first time in history that Fianna Fáil and Fine Gael were in the same government. The previous Taoiseach and leader of Fine Gael, Leo Varadkar, became the Tánaiste (deputy head of government). Martin led the country as Taoiseach until 17 December 2022, when he changed posts with Varadkar.

According to the V-Dem Democracy indices, Ireland was the 3rd most electoral democratic country in the world in 2024.

Constitution

The state operates under the Constitution of Ireland () which was adopted in 1937 by means of a plebiscite. The constitution falls within the liberal democratic tradition. It defines the organs of government and guarantees certain fundamental rights. The Constitution can only be amended by means of a referendum. Important constitutional referendums have concerned issues such as abortion, the status of the Catholic Church, divorce, the European Union and same-sex marriage.

President

The head of state is the President of Ireland. In keeping with the state's parliamentary system of government, the President exercises a mainly ceremonial role but does possess certain specific powers. The presidency is open to all Irish citizens who are at least 35. They are directly elected by secret ballot under the alternative vote. A candidate may be nominated for election as president by no fewer than 20 members of the Oireachtas or by four or more of Ireland's 31 County and City Councils. A retiring President may nominate themselves as a candidate for re-election. If only one valid candidate is nominated for election, for example if there is consensus among the political parties to nominate a single candidate, it is unnecessary to proceed to a ballot and that candidate is deemed elected. The President is elected to a seven-year term of office and no person may serve more than two terms.

In carrying out certain of their constitutional functions, the President is aided by the Council of State. There is no vice-president in Ireland. If for any reason the President is unable to carry out their functions, or if the Office of President is vacant, the duties of the President are carried out by the Presidential Commission.

The President may not veto bills passed by the Oireachtas but may, after consultation with the Council of State, refer them to the Supreme Court of Ireland for a ruling on whether they comply with the constitution. The President may refuse a request of the Taoiseach for a dissolution of Dáil Éireann, although no request for a dissolution has ever been refused.

Legislative branch

Article 15 of the Constitution of Ireland established the Oireachtas as the national parliament of Ireland. The Oireachtas consists of the President of Ireland and two elected houses: Dáil Éireann (the House of Representatives) and Seanad Éireann (the Senate). As the Oireachtas also consists of the President, the title of the two law-making houses is the Houses of the Oireachtas. The Dáil is by far the dominant house of the legislature.

Dáil Éireann

Members of the Dáil are directly elected at least once in every five years under the single transferable vote form of proportional representation from multi-seat constituencies. Membership of the house is open to all Irish citizens who are at least 21 and permanently resident in the State. The electorate consists of all Irish and British citizens resident in Ireland over the age of 18. Members of the Dáil are known as Teachta Dála or TDs. As of 2025, there are 174 TDs, of which one, the Ceann Comhairle (presiding officer), is automatically returned at an election. The Taoiseach, Tánaiste and the Minister for Finance must be members of the Dáil. The Dáil is the only House which can introduce and amend money bills (i.e. financial and tax legislation). Since the early 1980s, no single party has had a majority in Dáil Éireann, so that coalition governments have been the norm.

Seanad Éireann

The Seanad is a largely advisory body. It consists of sixty members called Senators. An election for the Seanad must take place no later than 90 days after a general election for the members of the Dáil. Eleven Senators are nominated by the Taoiseach while a further six are elected by certain national universities. The remaining 43 are elected from special vocational panels of candidates, the electorate for which consists of the 60 members of the outgoing Senate, the 174 TDs of the incoming Dáil and the 949 elected members of 31 local authorities. The Seanad has the power to delay legislative proposals and is allowed 90 days to consider and amend bills sent to it by the Dáil (excluding money bills). The Seanad is only allowed 21 days to consider money bills sent to it by the Dáil. The Seanad cannot amend money bills but can make recommendations to the Dáil on such bills. No more than two members of a government may be members of the Seanad, and only twice since 1937 have members of the Seanad been appointed to government.

Executive branch

Executive authority is exercised by a cabinet known simply as the Government. Article 28 of the Constitution states that the Government may consist of no less than seven and no more than fifteen members, namely the Taoiseach (prime minister), the Tánaiste (deputy prime minister) and up to thirteen other ministers. The Minister for Finance is the only other position named in the Constitution. The Taoiseach is appointed by the President, after being nominated by Dáil Éireann. The remaining ministers are nominated by the Taoiseach and appointed by the President following their approval by the Dáil. The Government must enjoy the confidence of Dáil Éireann and, in the event that they cease to enjoy the support of the lower house, the Taoiseach must either resign or request the President to dissolve the Dáil, in which case a general election follows.

Judicial branch

Ireland is a common law jurisdiction. The judiciary consists of the Supreme Court, the Court of Appeal and the High Court established by the Constitution and other lower courts established by statute law. Judges are appointed by the President after being nominated by the Government and can be removed from office only for misbehaviour or incapacity, and then only by resolution of both houses of the Oireachtas. The final court of appeal is the Supreme Court, which consists of the Chief Justice, nine ordinary judges and, the Presidents of the Court of Appeal and the High Court. The Supreme Court rarely sits as a full bench and normally hears cases in chambers of three, five or seven judges.

The courts established by the constitution have the power of judicial review and may declare to be invalid both laws and acts of the state which are repugnant to the constitution.

Public sector

The Government, through the civil and public services and state-sponsored bodies, is a significant employer in the state; these three sectors are often called the public sector. Management of these various bodies vary, for instance in the civil service there will be clearly defined routes and patterns whilst among public services a sponsoring minister or the Minister for Finance may appoint a board or commission. Commercial activities, where the state involves itself, are typically through the state-sponsored bodies which are usually organised in a similar fashion to private companies.

A 2005 report on public sector employment, showed that in June 2005 the numbers employed in the public sector stood at 350,100; of these by sector they were 38,700 (civil service), 254,100 (public service) and 57,300 (state-sponsored). The total workforce of the state was 1,857,400 that year, thus the public sector represents approximately 20% of the total workforce.

Civil service

The Civil Service of Ireland consists of two broad components, the Civil Service of the Government and the Civil Service of the State. Whilst these two components are largely theoretical, they do have some fundamental operational differences. The Civil Service is expected to maintain the political impartiality in its work, and some sections of it are entirely independent of government decision making.

Public service

The public service is a relatively broad term and is not clearly defined and sometimes is taken to include the civil service. The public service proper consists of government agencies and bodies which provide services on behalf of the government but are not the core civil service. For instance local authorities, Education and Training Boards and Garda Síochána are considered to be public services.

Local government

Article 28A of the constitution of Ireland provides a constitutional basis for local government. The Oireachtas is empowered to establish the number, size and powers of local authorities by law. Under Article 28A, members of local authorities must be directly elected by voters at least once every five years.

Local government in Ireland is governed by a series of Local Government Acts, beginning with the Local Government (Ireland) Act 1898. The most significant of these is the Local Government Act 2001, which established a two-tier structure of local government. The Local Government Reform Act 2014 abolished the bottom tier, the town councils, leaving 31 local authorities. There are 26 County Councils (County Dublin having been divided into three council areas), 3 City Councils (Dublin, Cork and Galway), and 2 City and County Councils (Limerick and Waterford).

Political parties