Overview
Undersecretary (or under secretary) is a title for a person who works for and has a lower rank than a secretary (person in charge). It is used in the executive branch of government, with different meanings in different political systems, and is also used in other organizational settings.
In government, the position may be a junior government minister (e.g. a parliamentary secretary) who assists a secretary of state. In other cases, the position may be a senior government official, frequently a career public servant, who typically acts as a senior administrator. The senior administrator may be considered a second-in-command to a politically appointed cabinet minister or other government official (e.g. in the United States), or they may be considered a head or chief executive of a government department (e.g. a permanent secretary). Some systems of government have both types of position, as in the United Kingdom where the title has been in use since the 17th century.
Holy See
In the Holy See, undersecretary is a title given to senior administrative officials working in the dicasteries of the Roman Curia.
Hong Kong
In Hong Kong, undersecretary is a position created in 2008 to work closely with bureau secretaries and top civil servants to implement the Chief Executive's policy blueprint and agenda in an executive-led government. The appointment of undersecretaries and political assistants is an extension of the Principal Officials Accountability System into today's Political Appointments System.
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