The growing interest for the urban level of the sustainable development derives from not only a lot of studies of researchers about the processes of the local development but also the growing attention on the environmental effects of urban activities. In fact cities cause many pollutions and damages on the environment and so the urban planning acquires a particular meaning to avoid an economic development not compatible with the environment. The responsibility of the cities in causing environmental damages and widespread bad way of life has imposed a stop or a re-thinking about the urban management. In this paper the author will deal with the changes in the urban planning in the Sicilian region to lead cities according the principles of sustainable development.