The management of international rivers is increasingly marked by a heightened attention to and growth in institutions at the river-basin level to promote cooperation and resolve conflicts between states in a basin. Yet, little theoretical and empirical research exists to understand when these institutions are most effective. Here we draw from diverse literatures, including work on social and ecological systems, international institutions, common-pool resources, and international waters, to capture and integrate the design elements associated with effective collaborative management along an international river. We apply and test the validity of our model in a plausibility probe through the analysis of the conflict between Argentina and Uruguay over the construction of pulp mills along the Uruguay River, and the role of the established and functioning river basin organization—the Administrative Commission of the Uruguay River (CARU)—in this conflict. We re-examine our model based on our case findings to highlight the challenge and role of public input and representation in institutional effectiveness along international rivers.

Increased international attention to water resource management and integration has resulted in the creation of new institutional arrangements and environmental funding mechanisms. The Global Environmental Facility's (GEF) International Waters Program is at the heart of such novel collaborative approaches to managing transboundary resources. This paper assesses GEF-led efforts in twenty-three projects across ten geographic regions. It finds that the GEF has been successful in building scientific knowledge and creating linkages across social, economic and environmental issues. However, challenges of enhancing the contractual environment and building national capacity remain. While GEF efforts thus far do indicate that institutions can affect the growth of knowledge and cooperation around transboundary waters, long-lasting achievements of the GEF's International Waters Program have yet to be realized.