If the question of communism is making a comeback today, this renewed interest is often accompanied by an abandonment of any concrete political perspective. Critical philosophies are flourishing and proliferating, but, folded into the academic terrain, they often remain disconnected from the global issues associated with the present crisis of capitalism, contributing, in turn, to the fragmentation of the resistances that are opposed to it. Instead of locking the perspective of emancipation into the registers of utopia, or relegating it to the side of an empty populism, Isabelle Garo studies in this book the conditions of a contemporary revival of the alternative as a collective construction, anchored in real aspirations and struggles and inseparable from a rethinking of the theoretical work. By addressing the impasses faced by many of the most fashionable radical theorists - Badiou, Laclau, the theorists of the commons, and revisiting them in relation to Marx and Gramsci also allows us to re-read the latter from the point of view of contemporary questions of the state and the party, of work and property, of conflict and hegemony. Thus, to rethink strategy is above all to re-explore the question of mediations, whether they be forms of organisation or existing mobilisations, as sites par excellence of political invention.