Problems relating to the non-navigational uses of international watercourses have the capacity to be among the most serious causes of international conflicts in the 21st century. The Convention adopted by the UN General Assembly on 21 May 1997 is an attempt to provide at the universal level a coherent set of rules for the avoidance, management and settlement of such conflicts. This book gives a brief history of the codification process leading to the adoption of the Convention and considers the conflicting approaches to the subject that have been taken over the years. It examines the Convention as future treaty law and considers its impact on customary law putting it in the context of existing relevant international instruments. It analyzes the substantive principles of equitable utilization and of no-harm, on the one hand, and the procedural obligations, on the other, and emphasises their mutual complementarity.