The Academy is an institution for the study and teaching of Public and Private International Law and related subjects. Its purpose is to encourage a thorough and impartial examination of the problems arising from international relations in the field of law. The courses deal with the theoretical and practical aspects of the subject, including legislation and case law. All courses at the Academy are, in principle, published in the language in which they were delivered in the Collected Courses of the Hague Academy of International Law. Conflicts of Nationality (Statelessness and Dual Nationality) It is not unusual any more for individuals to have several nationalities, nor eventually to be deprived of any nationality. Today, situations of dual nationality or of statelessness tend indeed to increase. At the same time, some concepts of supra-nationality (e.g., the emergence of the European Union citizenship) or infra-nationality are being developed. The primary purpose of this article is to present new features of those legal problems, whose nature, forms and effects are more complex than in the past. It also discusses the legal solutions offered to those problems today, either within the framework of States (constitutions, statutes, case law etc.) or within the international legal order (treaties, international tribunals, and courts etc.).