Urban conservation has evolved in the past fifty years from a practice limited to a small number of historic areas, mostly in the European context, to a universally recognized area of urban policy-making, encompassing not only the traditional ‘old centres’ of many large cities or the preserved examples of small historic towns, but a greater variety of situations, including modern cities of significant value.Parallel to the expansion of the practice, the concept of historic city and the approach to its conservation has evolved, from a vision of the historic city as a monumental ensemble, to a more articulated vision that includes other value systems, linked to the archeological or geological layers, to the intangible dimensions of heritage and to the social composition of the city. 

Urban conservation has evolved in the past fifty years from a practice limited to a small number of historic areas, mostly in the European context, to a universally recognized area of urban policy-making, encompassing not only the traditional ‘old centres’ of many large cities or the preserved examples of small historic towns, but a greater variety of situations, including modern cities of significant value.Parallel to the expansion of the practice, the concept of historic city and the approach to its conservation has evolved, from a vision of the historic city as a monumental ensemble, to a more articulated vision that includes other value systems, linked to the archeological or geological layers, to the intangible dimensions of heritage and to the social composition of the city.