The Taoiseach (; ), plural Taoisigh ( or ), also referred to as An Taoiseach (), is the prime minister and head of government of Ireland. The Taoiseach is appointed by the President upon the nomination of Dáil Éireann (the lower house of the Oireachtas), and must, while he remains in office, retain the support of a majority in the Dáil. 
Under the Constitution of Ireland the Taoiseach must be appointed from among the members of Dáil Éireann. In the event that the Taoiseach loses the support of a majority in Dáil Éireann, he is not automatically removed from office but, rather, is compelled either to resign or to persuade the President to dissolve the Dáil. The President may refuse to grant a dissolution, and, in effect, force the Taoiseach to resign, but, to date, no president has exercised this prerogative (though the option arose in 1944 and 1994 and twice in 1982). The Taoiseach may lose the support of Dáil Éireann by the passage of a vote of no confidence, the failure of a vote of confidence or, alternatively, the Dáil may refuse supply. In the event of the Taoiseach's resignation, he continues to exercise the duties and functions of his office until the appointment of a successor.
The Taoiseach nominates the remaining members of the Government, who are then, with the consent of the Dáil, appointed by the President. The Taoiseach also has authority to have fellow members of the cabinet dismissed from office. He or she is further responsible for appointing eleven members of the Senate.
The Taoiseach's salary has been somewhat higher than for leaders in many other countries: €228,466 annually following a recent reduction of 20% on the previous €285,582, compared to £142,000 (about €172,164) for the British Prime Minister and €231,000 for the President of France. In October 2007, the Taoiseach was the highest-paid head of government in the OECD countries. However, the remuneration structures for Government of Ireland employees apparently mean that comparison with other countries are not useful and are discouraged by the Review Body on Higher Remuneration in the Public Sector. A proposed increase of €38,000 in 2007, was deferred when Brian Cowen became Taoiseach and in October 2008, the government announced a 10% salary cut for all ministers, including the Taoiseach. However this was a voluntary cut and the salaries remained nominally the same with ministers and Taoiseach essentially refusing 10% of their salary. This courted controversy in December 2009 when a salary cut of 20% was based on the higher figure before the refused amount was deducted. The Taoiseach is also allowed an additional €118,981 in annual expenses.
There is no official residence of the Taoiseach. However, in 2008 it was reported that the former Steward's Lodge at Farmleigh adjoining the Phoenix Park would become the official residence of the Taoiseach. The house, which forms part of the Farmleigh estate acquired by the State in 1999 for €29.2m, was renovated at a cost of nearly €600,000 in 2005 by the Office of Public Works. Former Taoiseach Bertie Ahern did not use it as a residence, however the current Taoiseach Brian Cowen, uses it "from time to time".