Fiji is divided administratively into four divisions, which are further subdivided into fourteen provinces; the self-governing island of Rotuma and its dependencies lie outside any of the four divisions. Each division is headed by a Commissioner, appointed by the Fijian government. The divisions are basically agglomerations of provinces and have few administrative functions of their own, but serve to foster cooperation among the member provinces for providing services. Each province has a provincial council which may make bylaws and impose rates (local taxes), subject to the approval of the Fijian Affairs Board, a government department. The board must also approve the appointment of the Roko Tui, or executive head of the provincial council, who is usually a high chief, although in recent years, commoners have sometimes been chosen.