A file of reports, correspondence and memoranda concerning the organisation of the Security Service (MI5). Documents and topics of discussion in this file include staff arrangements, including the appointment of a new director of the service; the retirement age for members of the service; attempts to make financial economies; a report containing arguments for and against the establishment of a new overseas division; an agreement with the Secret Intelligence Service (MI6) that at some point in the future the two services would move to a shared headquarters; a series of letters forming part of a dispute over the roles and responsibilities of the two services, in particular intelligence gathering and operations abroad; and a directive to the Director-General of MI5 outlining his duties and responsibilities.