The book aims to provide a theoretical overview of the most important areas of public international law, and it does so in the form of a collective work. Public International Law, as a scientific discipline notable for its growing quantitative and qualitative importance and its considerable technical-legal complexity, requires, for educational and investigative purposes, large doses of specialisation and rigour, and only through joint and coordinated work carried out in stable research groups will it be possible to tackle and overcome new teaching and research challenges