Water is increasingly perceived as a strategic resource for the twenty-first century. A new framework for the management of water resources in international river basins is necessary to overcome some of the persistent conflicts related to international rivers. This article provides a general description of transboundary issues related to international watercourses, with a focus on situations involving European Union Member States. The rapid evolution of environmental management concepts at the international and global levels will have a clear impact on the approaches adopted by the international community with respect to international rivers. New concepts, principles, and mechanisms are being developed to help incorporate all the complexity of environmental concerns in transboundary river management. Sustainable development, shared responsibility, hydrodiplomacy, subsidiarity, the epistemic communities' approach, and public involvement appear to be some of the keywords for the near future. Global agreements dealing with all aspects of water resources management should be put forward under a common general framework, and aspects of planning, management, and operation should be explicitly addressed in specific agreements. This is essential in order to achieve an adequate balance and integration between the social, environmental, technical, legal, and institutional dimensions of existing problems. The new Convention on Non-Navigational Uses of Water, being put forward by the United Nations, is a significant effort in this long and difficult process of solving water-related international disputes.