Nowaday, secession, seen as a peaceful or violent process by which a part of the territory of an existing state breaks away from that state, seems to be a tendency of a global nature. The legal discussion regarding Kosovo's declaration of independence, as well as the act of "integration" of the Crimean peninsula into the Russian Federation, raises a whole series of questions, starting from the issue of the legality of secession, the process of state formation, the role international recognition and the extent to which the international community can intervene in such a process, the effectiveness of the present UN system. This article will be limited to the examination of some theoretical and practical aspects of secession, by reference to positive international law.