In Bosnia and Herzegovina the smallest administrative unit is the municipality ("opština/општина" or "općina/опћина" in the official languages and scripts of the country). Prior to the 1992–95 Bosnian War there were 109 municipalities in what was then Socialist Republic of Bosnia and Herzegovina. Ten of these formed the area of the capital Sarajevo.
After the war the number of municipalities was increased to 143, grouped in the following way:
In addition, Brčko District does not belong to either entity and is governed as a condominium of both FBiH and RS entities. The district corresponds to the pre-war Brčko municipality. Although technically not called a municipality, it is treated as such for statistic purposes.
Administratively each municipality has a municipality council and a municipality head, and they usually consist of an urban area with the surrounding villages and rural areas around it. Bosnia and Herzegovina also has twelve officially designated cities - Banja Luka, Bihać, Tuzla, Mostar, Zenica, Doboj, Prijedor Bijeljina, Trebinje and Široki Brijeg each correspond to a single eponymous municipality. The cities of Sarajevo and Istočno Sarajevo consist of four and six municipalities respectively, which roughly correspond to the ten pre-war municipalities which constituted the capital city.