In the 20th Century, non-parliamentary publications are either departmental publications published by HMSO but not part of the Sessional Papers or publications which are government documents but are not published by the Government publisher at all. To a greater extent than is currently the situation in the United States, the Government publisher has cut back on the number of documents it issues. A Treasury circular in 1921 made certain classes of documents that were once parliamentary non-parliamentary. Sometimes not all the documents relative to significant policy issues are published by HMSO. It is entirely possible that the final report of a royal commission will be published by HMSO, but not the evidence taken.
For historical research prior to the Internet era, to be sure to identify all the possible documents associated with a particular project, which make up its history, one must be sure to use the Stationery Office Annual Catalogue (Z 2009 .G822 Main) and its predecessors. The Breviates listed in Part II of this guide usually list all the documents associated with a problem or project also. One must also use the Stationery Office Annual Catalogue and its predecessors to identify department level publications. In addition, M.S.U. Libraries also has these other guides and indexes to this material:
Catalogue of British Official Publications not Published by HMSO. 1981. Z 2009 .C3 1980 Main
This is published by Chadwyck-Healey, a microfilming/digital publishing company. It includes publications from government departments, nationalized industries, research institutes, quasi governmental bodies, non-government organizations, and other official bodies whose work is not available from HMSO. The publications include periodicals, newspapers, serials, updates, leaflets, maps, posters, visual aids, etc. If M.S.U. Libraries owns any of these titles, the online catalog will indicate that.
Checklist of British Official Serial Publications. 1987. Z 2009 .B7 1987 Main
Arranged alphabetically by serial name, this source provides issuing agency name, frequency, and availability information for British government issued serials (periodicals). It includes titles issued by government departments and by bodies established, controlled, and/or financed by the government of the United Kingdom. It does not include reports, minutes, or proceedings of select committees of parliament, or the publications of nationalized industries, public corporations, bodies with only regional responsibilities, tourist boards, or museums and galleries.
For finding British documents published from the mid 1990s on, use of the Internet is essential. Here are some avenues into the departmental publications via online searching: