This volume collects the proceedings of the Conference sponsored by Regione Siciliana and Regione Autonoma di Sardegna, under the patronage of the Conference of Regions and Autonomous Provinces and the Islands Commission of the Conference of Maritime and Peripheral Regions (CMPR), at the Chamber of Deputies (Refectory Room of Palazzo S. Macuto) on December 10, 2021. In addition to this works, there are also some reflections held at the subsequent Seminar held on April 8, 2022, at the Rome headquarters of Regione Siciliana on the proposal: "The condition of insularity between Europe and Italy," with the intervention of the French MEP, Younous Omarjee, President of the Committee on Regional Development (REGI) of the EU Parliament.