1. For a detailed study of its growth see D. N. Chester and F. M. G. Willson, The Organisation of British Central Government, 1914–56 (Royal Institute of Public Administration, 1957); 2nd ed., 1914–64 (RIPA, 1968).
2. In March 1974 the newly separate Minister of Overseas Development was outside the Cabinet. In June 1975 the Secretary of State for Foreign and Commonwealth Affairs was given the additional title of Minister of Overseas Development: at the same time Mr Reg Prentice, while retaining his seat in the Cabinet, became a Minister of State in the Foreign and Commonwealth Office with the title of Minister for Overseas Development and with responsibility delegated by the Secretary of State to run the separate Department of Overseas Development. On Mr Prentice’s resignation from the Government in December 1976 the post reverted to one held outside the Cabinet but still with the status of a Minister of State at the Foreign and Commonwealth Office and the same title and departmental jurisdiction.
3. The Northern Ireland Office, which was established early in 1972 as a result of the decision to dismantle the Stormont system, makes a comparison of total major departments a little unfair. Nineteen would be the more strictly comparable number to that of fifteen in 1971.
4. A very convenient source of numbers at 1 April 1973 is an appendix to the essay by Sir Richard Clarke on ‘The Machinery of Government’, in Wm. Thornhill (ed.), The Modernization of British Government (London, 1975).
5. An early and still highly relevant analysis of the phenomenon was contributed by D. N. Chester, ‘Double Banking and Deputy Ministers’, in New Society, 11 June 1964.