A national programme of Historic Landscape Characterisation was initiated by English Heritage in the early 1990s, to improve understanding of the historic dimension of landscape and thus better manage change in this valuable resource. All landscape within the British Isles can be said to be historic - there are hardly any areas, even apparently 'natural' ones, which man has not utilised or affected. The term historic landscape is therefore taken to encompass not just archaeological monuments and historic sites and buildings, but also roads and open spaces, fields, hedgerows, woodland and other habitats.

Over the past decade, HLC has evolved; there have been several 'waves' of the programme, each project developing and adapting the method to its own area. The recent method review undertaken by Aldred and Fairclough in 2003 gives a useful summary of this history.

The method was first pioneered in Cornwall in 1993-9. In the last couple of years, progress has been rapid, particularly in the development of Geographic Information System (GIS) tables. The most recent approaches have adopted a multi mode approach. This uses both descriptive and prescriptive criteria, but their subjectivity is controlled and made transparent. Interpretations and observations are attached to GIS map polygons instead of being used to allocate land to pre-defined types. The Cranborne Chase and West Wiltshire Downs AONB HLC follows one of these more recent approaches.

Despite the growing sophistication of GIS, HLC is a relatively generalised characterisation designed to serve as a resource management tool. It is not free-standing, or a replacement for other established datasets (such as Sites and Monument Record's/Historic Environment Records or other landscape assessments) but fills a gap in the available range of conservation mechanisms. The overall characterisation of the country provides an inclusive, comprehensive framework for conservation and management - there should be no 'white areas' on a map where the historical dimension is omitted. This broad approach is repeatable and updateable, and enables more detailed assessment to be carried out when required.