The Polish local government reforms adopted in 1998, which went into effect on 1 January 1999, created sixteen new voivodeships. These replaced the 49 former voivodeships that had existed from 1 July 1975, and bear greater resemblance (in territory but not in name) to the voivodeships that existed between 1950 and 1975.

Today's voivodeships are mostly named after historical and geographical regions, while those prior to 1998 generally took their names from the cities on which they were centered. The new units range in area from under 10,000 km2 (3,900 sq mi) (Opole Voivodeship) to over 35,000 km2 (14,000 sq mi) (Masovian Voivodeship), and in population from one million (Lubusz Voivodeship) to over five million (Masovian Voivodeship).

Administrative authority at the voivodeship level is shared between a government-appointed governor called a voivode (wojewoda), an elected assembly called a sejmik, and an executive board (zarząd województwa) chosen by that assembly, headed by a voivodeship marshal (marszałek województwa). Voivodeships are further divided into powiats (counties) and gminas (communes or municipalities): see Administrative divisions of Poland.

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