This work presents a critical history of the development of the concept of nationality in Italian law and a critical appraisal of its role in Italian law today, concluding by questioning its contemporary value. Part One sketches the development of restrictions on the ownership and disposition of merchant ships in European states from mediaeval times to the early 18th century. The heavy influence which French law has had upon Italian law is reflected in an examination of the development of French law through the revolutionary period and in the Napoleonic age. Part Two is predominantly concerned with the development of the concept of nationality in the emergent nation of Italy and the codification of 1865. In this historical survey Professor d’Alessio is concerned to explain the development of the concept of the nationality of the ship in the context of the strong nationalistic climate of 19th century Italy, when nationality became a key jurisprudential concept in continental European law under the guidance of Mancini. Part Three takes us from the background to the Code of Navigation of 1942, which still forms the basis of the law on the nationality of ships to the present day. The author is careful to place legal developments in their wider political and economic context, showing for example conflict between liberalism and protectionism, between the desire to attract foreign capital and the wish to maintain a strong national merchant fleet serving national interests. Professor d’Alessio gives a detailed critique of Law No. 723 of 9 December 1975, amending Art. 143 of the Code of Navigation. In particular this enabled foreigners to