Since 1945, in particular, many studies have been written in the field of maritime delimitation. Most of them have focused on the case law. In fact, as is shown in the bibliography, there are many articles relating to international judgments in this field. Since it has been argued that the law of maritime delimitation has developed through international jurisprudence, it was only natural that writers turned to the analysis of case law in this field.
By contrast, State practice concerning maritime delimitation has not been sufficiently studied until recently. This situation seems to be understandable due to the difficulties of systematic research in State practice on maritime delimitation and the lack of information regarding the negotiation processes necessary to reach agreements. These difficulties remain to this day. Recently, however, studies on world wide and regional State practice concerning maritime boundaries are developing. Regarding the world-wide study of State practice, the publication of International Maritime Boundaries by the American Society of International Law is the most important development. With respect to regional State practice on maritime delimitation, regional maritime areas in the world have been examined by regional experts. These areas include: South-East Asia; the China Seas; the Mediterranean Sea; the Russian region; the Persian Gulf; the Caribbean Sea; and the Pacific. Owing to the development of studies regarding world-wide and regional State practice, it becomes possible, to a certain extent, to examine State practice systematically.
Therefore, at present, it is essential to specify the present-day law of maritime delimitation by studying not only the case law but also State practice.
Some writers examined the subject starting in the 1980s. So far as monographs are concerned, studies by Jagota, Johnston, Weil, Evans, Tanja and Lucchini and Voelckel are in particular pioneers in this field. Despite the work of these writers, it appears that the law of maritime delimitation is still in a state of flux. In order to break down the situation, it is necessary to clarify the essence of the law of maritime delimitation and to present a proper legal framework for that law on the basis of case law, recent State practice and opinions of writers.
