An urban growth boundary, or UGB, is a regional boundary, set in an attempt to control urban sprawl by, in its simplest form, mandating that the area inside the boundary be used for urban development and the area outside be preserved in its natural state or used for agriculture. Legislating for an "urban growth boundary" is one way, among many others, of managing the major challenges posed by unplanned urban growth and the encroachment of cities upon agricultural and rural land. An urban growth boundary circumscribes an entire urbanized area and is used by local governments as a guide to zoning and land use decisions, and by utilities and other infrastructure providers to improve efficiency through effective long term planning (e.g. optimising sewerage catchments, school districts, etc.). If the area affected by the boundary includes multiple jurisdictions a special urban planning agency may be created by the state or regional government to manage the boundary. In a rural context, the terms town boundary, village curtilage or village envelope may be used to apply the same constraining principles. Some jurisdictions refer to the area within an urban growth boundary as an urban growth area (UGA) or urban service area, etc. While the names are different, the concept is the same. History Opposition to unregulated urban growth and ribbon development began to grow towards the end of the 19th century in England. The campaign group Campaign to Protect Rural England (CPRE) was formed in 1926 and exerted environmentalist pressure. Implementation of the notion dated from Herbert Morrison's 1934 leadership of the London County Council. It was first formally proposed by the Greater London Regional Planning Committee in 1935, "to provide a reserve supply of public open spaces and of recreational areas and to establish a green belt or girdle of open space". New provisions for compensation in the 1947 Town and Country Planning Act allowed local authorities around the country to incorporate green belt proposals in their first development plans. The codification of Green Belt policy and its extension to areas other than London came with the historic Circular 42/55 inviting local planning authorities to consider the establishment of Green Belts. In the United States, the first urban growth boundary was established in 1958, around the city of Lexington, Kentucky. Lexington's population was expanding, and city leaders were concerned about the survival of the surrounding horse farms closely tied to the city's