This book discusses the fundamental issues of public law in the area of statelessness from the perspectives of comparative law and international law standards. The author proposes an approach in which statelessness is not a homogeneous concept but is best analysed and responded to through the lens of different categories of statelessness. This accounts not only for the existence of different categories of stateless persons (e.g., voluntary or involuntary) but also for different assessments and needs of their respective situations for purposes such as prevention mechanisms. The book demonstrates the conceptual and regulatory relevance of this important differential aspect of the international law on statelessness (with implications for domestic legal systems).