Although the recognition of States is a common occurrence in international relations and still retains a central position in discussions of international law, its nature and legal effects remain controversial well into the twenty-first century. Regardless of whether recognition is said to play a fundamental role in the creation of statehood or is denied any legal value at all, debates surrounding any case where statehood is disputed will sooner or later turn to the matter of recognition, or lack thereof, by other States. This book challenges the widespread view of statehood as an absolute or empirical fact and of recognition as merely declaratory in the creation of States as the primary and original persons of international law. Drawing upon a comparative analysis of contested States ranging from Palestine and Kosovo to Somaliland and Eastern Ukraine, it builds a normative theory of recognition that sets out the legal value and effects of this act in various situations, distinguishing between cases where statehood may be inferred from applicable rules of international law, those where it could only be explained by recognition, and those where the establishment of a State is prevented by international legal norms. In addition to discussing a range of issues related to recognition, this work provides an up-to-date overview of the most important international and domestic case-law and practice and includes reflections on various cases of contested statehood around the world.