The Garda Commissioner – officially known as the Commissioner of An Garda Síochána – is the head of the Garda Síochána, the national police force of Ireland. The Garda Commissioner is appointed by the Government of Ireland (Cabinet), on the recommendation of the Minister for Justice. The Commissioner reports to the Minister for Justice, in charge of the Department of Justice, of which the Garda Síochána is a state agency. The Garda Commissioner sits on the Irish Government's National Security Committee (NSC), and is responsible for Ireland's domestic state security apparatus.

The National Security Committee (NSC) of Ireland is a secretive inter-departmental committee responsible for ensuring that the Taoiseach and Government of Ireland are kept informed of high-level national security, intelligence and defence issues, and the state's response to them.