British treaties and agreements of international effect (including unratified treaties) are published as Command Papers, which fall under the category of State Papers. Command Papers are laid before Parliament and form part of the Parliamentary Papers for each session.
Treaties are cataloged and indexed by the relevant government departments and official bodies. While historically published and indexed by Her Majesty's Stationery Office (HMSO), the commercial publisher of the official printed version of the Command Papers is now The Stationery Office (TSO), and the management of Crown copyright and official information functions formerly held by the Office of Public Sector Information (OPSI) have largely transferred to The National Archives.