The end of the Cold War brought about new secessionist aspirations and the strengthening and re-awakening of existing or dormant separatist claims everywhere. The creation of a new independent entity through the separation of part of the territory and population of an existing State raises serious difficulties as to the role of international law. This book offers a comprehensive study of secession from an international law perspective, focusing on practice and applicable rules of international law. It includes theoretical analyses and a scrutiny of practice throughout the world by eighteen distinguished authors from Western and Eastern Europe, North and Sub-Saharan Africa, North and Latin America, and Asia. Core questions are addressed from different perspectives, and in some cases with divergent views. The reader is also exposed to a far-reaching picture of State practice, including some cases which are rarely mentioned and often neglected in scholarly analysis of secession.