The aim of this paper is to discuss the dualism between centre and periphery, which has characterized the debate on development and modernisation of the backward regions. The author underlines the analytical need to complicate the opposition between centre and periphery, because of the increasing differentiation of the socio-economic reality. She examines the case of Southern Italy, as the Italian periphery, which the mainstream considers an undifferentiated underdevelopment macro-region. Given a series of obstacles related to both economic markets and national policies, the local production systems can reaction in many different ways, affected by social, cultural and political local contexts. The author proposes an interpretation of these differences in the southern Italian regions and introduces the concepts of social cohesion and political cohesion, whose implications for local economic development she tries to deepen.