Disagreements or full-fledged disputes continue to exist in international river basins even after the establishment of river basin organizations (RBOs) — originally often established to solve, mitigate, or prevent such disputes. However, research on transboundary river basin management as well as empirical evidence from basins around the world suggests that RBOs do make a difference by providing mechanisms for dispute resolution. This chapter asks whether and how RBOs engage in the solution of disputes that arise over water resources in transboundary basins. The chapter provides an overview of the global distribution of different RBO conflict-resolution mechanisms and analyzes in greater detail two conflict cases: the Mekong and the Nile rivers. While the findings reveal that the existence of specific conflict-resolution mechanisms does not necessarily influence the effectiveness of dispute resolution, RBOs as a whole do matter in addressing water-related conflicts through a range of mechanisms beyond pure dispute-resolution mechanisms, including the provision of forums for negotiation and exchange, data and information, or notification procedures.