International fluvial law is one branch of international law that presents thestudent of international law with a seemingly irreconcilable paradox. On the one hand, judging from the scanty treatment often given to the issue in the standard treatises (and its almost complete absence from college syllabi), one could easily conclude that international fluvial law is only to be located on the periphery of international law; that it is a fringe subject, just as air law and space law were regarded only half a century ago. But, on the other hand, a more patient enquiry into the history and development of international law soon reveals that, in fact, international law has been concerned with the regulation of international watercourses (lakes, rivers, etc.,) for a long time, with individual pronouncements by publicists dating back to the writings of the acclaimed ‘fathers’ of international law: Grotius, Pufendorf and Vattel. Viewed from this angle, then, international fluvial law, or the law of international watercourses, lies at the very core, rather than on the fringes, of the historical development of international law. Indeed, it is apt to observe that the history of the modern international organization, and thus the advent of the law of international institutions, dates back to the establishment of the various international commissions by European States in respect of some of the major international rivers in Europe between 1815 and 1866: the Rhine Commission (1815), the European Commission for the Danube (1856) and those dealing with the Elbe (1821), the Douro (1835), the Po (1849) and the Pruth (1866).