This chapter works out what seems to be a paradox: secession, a process of splitting and division of Member States can lead to strengthening solidarity. The research question is whether a claim of secession contravenes per se the founding European value of solidarity enshrined in Article 2 (TEU). After a brief introduction, the chapter analyses the concept of secession, its meanings, effects and moral implications of a process of withdrawing from a EU Member State. It follows by analysing the concept of solidarity and its EU legal-politico perspectives. It finally concludes by presenting an alternative vision to the dominant presumption that considers that self-determination from a democratic state implies necessarily an egoist economic and political reason.