The question of whether class or territory is the stronger basis of social mobilisation is examined. It is suggested that the economic problems being experienced by many older industrial areas can give rise to regional coalitions that seek to transcend class antagonisms in order to press for state investment to improve regional growth and employment prospects. But it is further argued that, because of the heterogeneity of the sociospatial base in such regions, supralocal coalitions will be vulnerable to the effects of allocative decisions favouring particular within-region locations. The notion of the vulnerability of regional social bases to the expression of local class interests is explored in the context of industrial South Wales. This region has been subject to successive attempts at economic revival, often in response to an apparently coherent regional voice pressing for state regional interventions. Important parts of various policies for restructuring the regional economy have been defeated in the past, precisely because of the impotence of regional coalitions to carry disadvantaged local class groupings along with them. On occasions, such local class groupings have been capable of mobilising popular support, indicating more the defensive than offensive nature of their power.