Without rules on maritime delimitation in marine spaces where the jurisdiction of coastal states overlaps, the legal uses of these spaces cannot be enjoyed effectively. In this sense, the international law of maritime delimitation is of central importance. There is no doubt that international courts and tribunals play an important role in developing the international law of maritime delimitation. Hence it is important to analyze the development of case law in this field. This article examines the maritime delimitation between Romania and Ukraine in the Black Sea before the International Court of Justice. After reviewing the delimitation process in the Romania/Ukraine case, this article will address three principal issues: methodology of maritime delimitations, baseline issues and questions concerning the disproportionality test.