"On 16 November 2024, the United Nations Convention on the Law of the Sea (UNCLOS) celebrates the thirtieth anniversary of its entry into force. It is both a significant milestone and an opportunity to take stock of the Convention's implementation and effectiveness. It is in this spirit that we have prepared and published this work. The adoption and opening for signature of this treaty, on 10 December 1982, marked the end of twenty-seven long years of intense international negotiations. With its universal acceptance and comprehensive scope, it has endowed the law of the sea with unity, coherence and a remarkable degree of institutionalization. In short, UNCLOS has provided the international community with a treaty covering 'all matters relating to the law of the sea'. A veritable 'Constitution for the seas and oceans', as a result of its scope, it is hierarchically superior to any other maritime treaty. It was a fundamental step towards a new international order. A review of the three decades that have elapsed since UNCLOS entered into force shows that - notwithstanding the tensions that arose in the early years of its existence, which necessitated the adoption, on 28 July 1994, of the Agreement relating to the Implementation of Part XI of the Convention of 10 December 1982 to facilitate its entry into force-UNCLOS has been a great success. First, it was widely supported by the international community, with more than one hundred states signing it immediately after its adoption and opening for signature. Second, as a result of the very large number of States Parties it now has, it is of an (almost) universal nature.