In the administration of public affairs in Great Britain, several government departments have found it convenient to divide the country into varying numbers of regional districts, each covering a group of counties. These districts vary a good deal in number and in area for the different departments, though in some cases a similar area is used by more than one department. The largest area is Scotland, with an extensive organization of public administration under the Secretary of State for Scotland, and its own judicial system, while other departments also have branch headquarters for Scotland. Northern Ireland forms another important region, with a large degree of autonomy, under a separate parliament; while, as in the case of Scotland, several departments of the United Kingdom have branch headquarters in Belfast. Wales is also a distinct district for several departments.