Sir: I can confirm that the information given to David Turner (letter, 4 October) was correct. M15 have begun a series of transfers of their older records to the Public Record Office, in line with the process routinely followed by other government departments. The first records to be transferred will be made available to the public in our reading rooms on 18 November. This first transfer, which contains virtually all surviving material for the period of the First World War, will indeed be followed by others for the inter-war period and the Second World War.
The Public Record Office does certainly not regard the exercise as a "sop", nor was this expression ever used to Mr Turner. We are very pleased indeed that the transfer of MI5 files, a process which has been some time in the planning, is now under way.
Public Record Office
Kew, Richmond, Surrey