Her Majesty's Stationery Office

The Office of Public Sector Information (OPSI) is the body responsible for the operation of Her Majesty's Stationery Office (usually abbreviated as HMSO) and of other public information services of the United Kingdom. OPSI is part of the National Archives of the United Kingdom and it is responsible for Crown copyright.

OPSI announced on 21 June 2006 that it was merging with the National Archives. This merger took place in October 2006. OPSI continues to discharge its roles and responsibilities from within the structure of the National Archives.

The Controller of HMSO is also the Director of OPSI. HMSO continues to operate from within the expanded remit of OPSI. The Controller of HMSO also holds the offices of Queen's Printer of Acts of Parliament, Queen's Printer for Scotland and Government Printer for Northern Ireland.

By virtue of holding these offices OPSI publishes, through HMSO, the London Gazette, Edinburgh Gazette, Belfast Gazette and all legislation in the United Kingdom, including Acts of Parliament, Acts of the Scottish Parliament and Statutory Instruments.

The Controller of HMSO is appointed by Letters Patent to the office of Queen's Printer of Acts of Parliament. This office is separate from the functions of OPSI. Historically the role of Queen's (or King's) Printer extended to other official publishing responsibilities, e.g. the rights to print, publish and import the King James Bible and Book of Common Prayer within England, Wales and Northern Ireland. The current holder of this office is Cambridge University Press.

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