This chapter sums up the main arguments and findings of the book. It argues that although political differentiation in the EU is not new, the increasing differentiation after the Eurozone crisis and the asymmetric power relations between the EU and the associated non-members, lead to dominance. Neither segmentation nor hegemony leaves the democratic chain of rule intact. Political differentiation may end up in differentiated disintegration, and hence with a less integrated Europe—a more primitive form of association—with no effective polity to produce European public goods. Thus, integration, under conditions of compounding interdependence and economic integration, amounts to a categorical imperative.