According to a consolidated geo-historical pattern, Milan represents the core of a highly integrated metropolitan agglomeration situated at the centre of the polycentric urban system of 'Padania'. In the course of the centuries - and especially since the industrial age, as this pattern turned into the foundation for Milan's role as 'Italy's economic capital' (Dalmasso, 1972) - the area has developed strong complementary relations between the central city, with its superior 'metropolitan' functions, and its peripheral territorial systems, featuring relatively autonomous paths of socio-economic development.
While traditionally the origin of Milan's fortunes as a complete, internally balanced and functionally differentiated economic region, such a pattern of socio-economic and spatial integration has given rise in recent decades to new emerging phenomena, which have challenged traditional views of monocentric metro-politanisation processes. Geographic research has drawn attention to the variety of specific socio-economic and territorial production systems that lie behind the aggregate levels of performance of the Milan economic region as a whole. Reinterpreting the metropolitan region as a 'territory of differences' (e.g. Lanzani, 1991; Boeri et al., 1993; Palermo, 1997) has led in particular to an appreciation of the intense dynamics of intra-peripheral relations of a non-centripetal kind that have developed in the area. This kind of relationships involves a plurality of 'territorial systems' that feature recognisable individual patterns of spatial and economic development, establishing increasingly complex patterns of autonomy and interdependence with the metropolitan core. Accordingly, the increasing attention to 'local' dimensions of development has highlighted the need for more differentiated, area-based approaches to spatial policy, contributing to a critical revision of comprehensive approaches to metropolitan government and planning.
In light of recent geographical analyses of its features of internal socio-economic differentiation, the traditional inadequacy of references to administrative regions for addressing issues of governance in the Milan area becomes even more apparent. The provincial territory, in particular, has been traditionally inadequate in accounting for the complexity of its internal functional relations. Even if recent detachment