This paper addresses the increasing socio-spatial inequalities in European cities and their impact on the possibilities for fostering social cohesion. Many policy programmes tackle spatial unevenness in order to build more cohesive communities. These policies have some impact, but their effect on reducing inequalities at city level is limited. Therefore, an important question is how the overall socio-spatial organisation of European cities affects social cohesion and the capacity to form an urban community able to decide on a common future. First, the complex relation between present-day societal and spatial dynamics is discussed, asserting that it produces segregation. The second part reflects on how segregation is regarded in terms of social cohesion. Many authors stress the social innovative capacities within segregated areas. However, European cities display different socio-spatial structures. How these structures influence negotiation processes between different social groups is poorly treated. The last part of the paper addresses this issue.