The direction is entrusted to one of the most prestigious scholars of the Byzantine world, co-author with the celebrated Alexander P. Kazhdan in 1997 of the monumental volume on the aristocracy of Byzantium. The School intends to make a significant contribution to the knowledge of the greatest Mediterranean empire of the Middle Ages, focusing on the social core of its political organisation, analysing the differences with the Western world and the affinities with the Eastern world.