A permanent secretary is the most senior civil servant of a department or ministry charged with running the department or ministry's day-to-day activities. Permanent secretaries are the non-political civil service chief executives of government departments or ministries, who generally hold their position for a number of years (thus "permanent") at a ministry as distinct from the changing political secretaries of state to whom they report and provide advice. The role originated in the civil service of the United Kingdom and has been adopted in several Commonwealth countries as well as other countries influenced by the Westminster system.

In Australia, the position is called the "department secretary", “secretary of the department”, or “director-general of the department” in some states and territories.

In Canada, the senior civil service position is a "deputy minister", who within a government ministry or department is outranked only by a minister of the Crown. Federally, deputy ministers are appointed by the prime minister on the advice of the secretary to the cabinet (the Head of Canada's civil service). They are considered to hold equal rank with parliamentary secretaries or assistants – legislators appointed to assist ministers in their duties – and are entitled to several privileges, including the use of diplomatic passports.

In Germany, the equivalent office is called "Staatssekretär" (state secretary). It is not to be confused with the "parliamentary state secretary", who serves as deputy to a minister, often with a more specialised field of responsibilities. The parliamentary state secretary is always a political position, and not part of the civil service.

In Hong Kong, heads of policy bureaux, secretaries, were filled by civil servants until their titles were changed to permanent secretaries in 2002, when political appointees filled the positions of secretaries under the second Tung Chee Hwa government. Since August 2005, the Office of the Chief Executive also has a permanent secretary. His ranking is, however, lower than most other permanent secretaries according to the pay scale.

In India, the equivalent position is called "secretary to the Government of India" and is the highest-ranking permanent civil servant in a department. With the exception of departments within the Ministry of External Affairs, which are headed by Indian Foreign Service officers, all Secretaries to the Government of India are drawn from cadres of the Indian Administrative Service.

These officers directly report to Ministers of the Union within their respective ministry, and oversee all day-to-day operations of their departments. Within the civil service, they are outranked only by the Cabinet Secretary of India or the Principal Secretary to the Prime Minister of India when the latter is granted the rank of Cabinet Secretary (as has been the case under Prime Minister Narendra Modi).

In Indonesia, the equivalent position is called secretary-general (Indonesian: Sekretaris Jenderal, abbreviated Sekjen), one of the highest-ranking permanent civil servants in a ministry, leads the General Secretariat (Indonesian: Sekretariat Jenderal, abbreviated Setjen). These officers directly report to the minister in their respective ministry or to the respective leader in state bodies.