Dr David Jacques is a landscape historian and conservationist. He was influenced by the environmental movement of the early 1970s, and became committed to exploring the right relation between people and the land,, giving him an abiding interest in the history and theory of landscape. He has since written several books and numerous articles on garden and landscape history, for which he is perhaps best known. His first foray into landscape appreciation was in 1980 when he criticised the landscape-evaluation methods of the day, and his views on the topic developed when working on landscape-planning and highway-alignment projects, and also when inspector of parks and gardens for English Heritage. In the early 1990s he was central to the campaign to revise UNESCO's criteria for world-heritage sites to allow recognition of cultural landscapes, and in the 2010s has several times assisted the International Council for Monuments and Sites (ICOMOS) in its advice over nominations for them.