ABSTRACT
As a consequence of economic, technological and socio-cultural megatrends, the economic and social structure of urban society has changed and is still in motion. The internationalisation and informalisation of economies has changed the competitiveness of urban economies and powered the replacement of industrial economic functions by the service sector. The 'old' locations of economic functions in the city are often abandoned for new places of business in the suburbs. Also, lifestyles have evolved over the past decades, becoming less and less uniform. With the help of the private car, people's action spaces have expanded, becoming more differentiated among individuals. These changes are accompanied by serious economic, social and ecological problems which threaten the competitiveness and sustainability of cities.
