County commissioners are elected by voters residing in the county that the commissioners govern. Commissioner positions may be designated as at-large, or voted on by residents throughout the county. Commissioners can also represent voters in smaller geographical units, known as wards or districts.
Forms of county government in the United States vary. In Connecticut and Rhode Island, counties serve as geographical units, but have no county-level government. In the other 48 states, elected representatives serve on boards that provide county legislative authority. These representatives, most commonly known as commissioners or supervisors, may share power with an elected or appointed county executive.