This is a study of conservation and change throughout the built environment - city centres, suburbs, even villages - and how the activities of conservation interact with the planning system. It seeks to explore why, and what, change occurs, and who proposes and controls change, in areas of townscape that have been identified as worth conserving. Examining the key social, economic, and psychological ideas which support conservation, the book discusses various countries' conservation planning systems and the fundamental ideas that act as precendents to guide future practice.