The major expansion in the volume of parliamentary business in the last 30 years has produced an expansion in the size and duties of the staff of the House of Commons. The official permanent staff is appointed to serve the House as a whole, and is organised into six departments. The professional staffs of the new, departmentally- related select committees constitute one of the most interesting new developments, the most recent example of that pragmatic growth of the parliamentary staff which has also given it a somewhat fragmented structure.