The Cabinet Secretary is the most senior civil servant in the United Kingdom. He or she acts as the senior policy adviser to the Prime Minister and Cabinet and as the Secretary to the Cabinet, responsible to all Ministers for the running of Cabinet Government. The role is currently occupied by Jeremy Heywood, appointed in January 2012; in succession to Gus O'Donnell, 2005–2012. The position of Cabinet Secretary was created in 1916 for Maurice Hankey, when the existing secretariat of the Committee of Imperial Defence, headed by Hankey, became secretariat to a newly organised War Cabinet.