<P> Special districts (also known as special service districts, special district governments, limited purpose entities, or special - purpose districts in the United States) are independent, special - purpose governmental units that exist separately from local governments such as county, municipal, and township governments, with substantial administrative and fiscal independence . They are formed to perform a single function or a set of related functions . The term special district governments as defined by the U.S. Census Bureau excludes school districts . In 2007, the U.S. had more than 39,000 special district governments . </P> <P> The United States Census counts government units across all States . This includes "special districts ." To count the special districts the Census must define the special districts so as to address all such governmental entities across the broad spectrum of 50 states' definitions and interpretations . The Census's full definition is: </P>

Local governments that provide a single service or a closely related set of services are