Members of the government in charge of Department of State are designated Ministers of Government (before 1977 a Minister of State). For distinction, Ministers of State (known before 1977 as Parliamentary Secretaries) — informally called junior ministers — are not members of the Government, but assist the Government Ministers in their Departments. A minister without portfolio may be appointed to the Government who is not the head of a Department of State; this occurred during the period known in Ireland as the Emergency when Frank Aiken served as Minister for the Co-ordination of Defensive Measures from 1939 until 1945. The functions of government ministers are frequently transferred between departments during cabinet reshuffles or after elections. On occasion, a department of state will cease to exist, with its functions transferred to another department. Such defunct ministerial positions include the Ministers for Labour, Posts and Telegraphs, Public Service and Supplies.