As a unitary state, the key administrative unit in Bangladesh is the region (also referred to popularly as the district), of which there are 21 in all. For administrative convenience, regions are grouped into (and report through) six divisions (Barisal, Chittagong, Dhaka, Khulna, Rajshahi, and Sylhet), under a senior civil servant with the title of division commander (formerly commissioner).
Regions or districts are under the charge of a senior civil servant with the title of deputy commissioner; they are appointed by the national government and are vested with broad powers to collect revenues and taxes, assist in development activities, and maintain law and order. As of 1985, regions or districts were subdivided into zilas; in urban areas, these were further broken down into municipalities, wards, mohallas, and thanas, while in rural areas, the breakdown was into upazilas (sub-districts), unions, mouzas, and villages.
In 1997, Bangladesh reorganized its local government structure in rural areas. New legislation created a four-tier local government system: gram (village), union (collection of villages), upazila (subdistrict), and zila (district) councils. The purpose of this reorganization was to democratize government at the grass roots level in a process that, in theory at least, is nonpartisan. Elections for union parishads (councils) held in December 1997 created widespread interest, with particularly high levels of participation from women, both as candidates as well as voters. Other legislation made the upazila level the most important tier in local government, giving the upazila council power to collect revenue, prepare its own budget and hire its own employees. The restructuring of local government in Bangladesh is an ongoing process aimed at increasing popular participation in the governmental process.