Every municipality is required to maintain a publicly accessible zoning map indicating what parcels of property within the municipality may be used for what purpose. This map must be updated at least every five years. Every municipality is required by state law to have a zoning administrator who oversees the local government's regulatory scheme, and is generally the party responsible for bringing legal actions against zoning violators. Each municipality is also required to have a board of zoning appeals empowered to grant variances and settle boundary disputes. The standard for granting of variances is that the party requesting the variance faces an unnecessary hardship unique to that party, but that adjacent property will not suffer a substantial detriment, and the character of the district will not be changed. The board may also grant special use permits allowing a property owner to use a property for a purpose that is neither specifically permitted nor specifically prohibited within a particular zoning area, and such permits may be conditioned on the property owner making concessions such as improving roads leading into the property, providing street lighting in the area, or setting aside a certain amount of land for public use. The board of zoning appeals may be appealed to the local Circuit Court if such an appeal is filed within 30 days of the zoning board decision, and from there decisions may be appealed directly to the Virginia Supreme Court.