ABSTRACT
The urban expansion can be considered, in part, as a mere quantitative extension of the previous suburbanisation process, with a wider decentralisation of dwellings and related services and infrastructures. Traditional terms like "suburbs", "rurban", "sprawl" and "rural-urban fringe" are no longer appropriate to describe the new forms of outer urbanization. The main features of the new forms of outer urbanization in different European countries exemplify the evolution from a common urban expansion to the new reticular model. The massive decentralization of population and employment, with its suburbanization of housing, production and service activities, determines the spread of urban regions. In Italy, the urban sprawl has been given various names according to different analytical points of view. Urban governance has to build up a network of different local systems and to arrange a co-operative organization of them. A multi-centred urban pattern seems to be replacing the hierarchical organization of centres. Social and spatial fragmentation is increasing.
