In the British Constitution no reform is ever so radical that all relics of the superseded system are removed. According to the theory of the eighteenth century, the King appointed a minister to administer certain services on his behalf; the minister alone was responsible for the administration of those services, the appointment and dismissal of the staff, the handling of the funds placed at his (or the King's) disposal for those services, and the general control of the establishments under his charge. This idea has never completely disappeared. A department is a separate unit in which, in principle, the minister is responsible for providing the staff out of moneys provided by Parliament, for maintaining efficiency among that staff, and for advising the Queen about the decisions to be taken or, if necessary, for taking the decisions himself in the Queen's name. The reforms of two centuries have in some degree provided for co-ordination, have caused general principles to be laid down for all of ‘Her Majesty's Civil Establishments’, and have enabled the Treasury Ministers to intervene in matters which departmental ministers would have regarded as within their competence.

The King consulted some or all of his ‘confidential advisers’ in Cabinet Council, and gradually the power of decision passed from the King to the Cabinet, which thus obtained a power of co-ordination of policy.