Green Belt is
a planning policy tool which aims to prevent urban
sprawl by keeping land permanently open. Generally,
Green Belt comprises countryside which is used for
agriculture, forestry or other similar open uses. When
defined, Green Belt can shape patterns of development
and ensure that development occurs at locations which
have been allocated by local planning authorities.
However, the boundaries of the Green Belt can
exceptionally be changed to, for example, meet future
development needs
(Source: 1.4 and 2.7, PPG2, January 1995).
Greenfield is land that has not previously been developed. It includes forestry, agricultural land, and associated buildings that have been blended into the natural landscape.
Brownfield or previously developed land is land which is or was occupied by a permanent structure, including the curtilage of the developed land and any associated fixed surface infrastructure. There is, however, no presumption that land which has been previously developed is necessarily suitable for housing development nor that the whole of the curtilage should be developed (Source: Annex A, PPS3, November 2006).






