A permanent under-secretary of state, known informally as a permanent secretary, is the most senior civil servant of a ministry in the United Kingdom, charged with running the department on a day-to-day basis. Permanent secretaries are appointed under a scheme in which the prime minister has the final say in the recruitment process; since 2015, the PM chooses directly from a list created by the Civil Service Commissioners rather than only having a veto over the Commissioners' preferred candidate.[1][2]
Some permanent secretaries do not hold the position of permanent secretary but still hold that grade. The Transparency of Lobbying, Non-party Campaigning and Trade Union Administration Act 2014 explains that a permanent secretary, for the purposes of Section 2 of that Act, is a person serving in government in any of the following positions: Permanent Secretary, Second Permanent Secretary, Cabinet Secretary, Chief Executive of His Majesty's Revenue and Customs, Chief Medical Officer, Director of Public Prosecutions, First Parliamentary Counsel, Government Chief Scientific Adviser, Head of the Civil Service, or Prime Minister's Adviser for Europe and Global Issues.[3]
Similar offices, often employing different terms, exist in many other Westminster-style systems and in some other governments. In the United States, the equivalent position is a Deputy Secretary of an executive department, though British permanent secretaries are career civil servants whereas Deputy Secretaries are political appointees.