The European Union is in crisis. Economic crisis, but also political crisis and symbolic crisis: the citizens distrust Europe which does not have clear project anymore Our hypothesis is that the solidarity economy can contribute to the emergence of a new European, clear and mobilizing project. A project offering new socioeconomic perspectives to the European citizens and an attractive utopia. This text will take place in four phases. In a first part, we shall describe the exhaustion of paradigm liberal and the limits of paradigm keynesian. Secondly, we shall try hard to demonstrate the theoretical possibility of establishing new one paradigm. In the third time, we shall illustrate this possibility by revisiting, in the light of the European solidarity initiatives, three economic notions keys. Finally, in a last time, we shall try hard to show in what the solidarity economy, which makes some deliberation between equals the best means assign all resources, can contribute to bring)out the European construction of the current impasse.