Land use is governed by a set of regulations generally known as ordinances or municipal codes, which are authorized by the state's zoning enabling law. Within an ordinance is a list of land use designations commonly known as zoning. Each different type of zone has its own set of allowed uses. These are known as by-right uses. Then there is an extra set of uses known as special uses. To build a use that is listed as a special use, a special use permit (or conditional use permit) must be obtained.
An example of a special use permit may be found in a church applying for one to construct a church building in a residential neighborhood. Although the church building is not a residential building, the zoning law may allow for churches in the residential neighborhood if the local zoning authority may review the impact on the neighborhood. This process grants discretion to the local zoning authority to ensure that an acceptable land use does not disrupt the zoning scheme because of its particular location.
US Zoning Model Act
The Standard State Zoning Enabling Act allows special use permits based upon a finding of compatibility with surrounding areas and with developments already permitted under the general provisions of the ordinance.
If the local zoning authority grants a special-use permit that exceeds the discretion allowed to it, then an incidence of spot zoning may arise. Such discretion then may be attacked as ultra vires, and the special-use permit overturned as an unconstitutional violation of equal protection.
Special use permits are also required when a property has been deemed a "nonconforming use." A special use permit for a nonconforming use will allow the owner of a previously-compliant property to continue the existing use. This often arises when a property has been rezoned or amortized. Amortization is unconstitutional in many states, and is a controversial tool according to many property rights advocacy groups.
Special land-use permits are also issued by the U.S. Forest Service for the operation of ski areas and other recreational facilities in national forests. Special-use permits have also been issued for other purposes, such as in Alaska during the summer of 2015, when special fishing permits were issued to feed firefighters who had difficulty receiving supplies via land routes due to the forest fires that they were fighting in remote areas.
In broadcasting, a restricted service licence (UK) or special temporary authority (US) may be issued by a broadcasting authority for temporary changes or set-ups for a radio station or television station. This may be for a temporary LPFM station for a special event (an RSL), or for an unexpected situation such as having to operate at low power from an emergency radio antenna or radio tower after a disaster or major equipment failure (STA).