This volume collects the final results of the Research Project of Relevant National Interest (PRIN) “International Migrations, State, Sovereignty and Human Rights: Open Legal Issues” (2019-2024). Four research units have been financed by the Italian Ministry of University and Research to carry on the PRIN, namely the units of the following Universities: Salerno, Campania “Luigi Vanvitelli”, Bari “Aldo Moro”, and Teramo. The researchers have worked under the guidance of Angela Di Stasi, as principal Investigator, and Ida Caracciolo, Gianni Cellamare and Pietro Gargiulo, as associate Investigators. Adopting a multilevel and multidisciplinary approach, the book aims to explore existing and future trends in the development of migration policy from the local to the global level, highlighting the challenges and gaps in the protection of migrants, and providing concepts and empirical findings with implications also for practitioners and lawyers.