Governing and managing the allocation and use of freshwater has always been a complex and fraught undertaking. The challenges to effective and equitable management have been exacerbated by rising pressures on supplies caused by such drivers as population growth, urbanization and climate change. Moreover, vast quantities of water straddle international and other boundaries—four-fifths of the world’s largest river basins and hundreds of aquifers span such borders. This further complicates management and governance, which is subject to disparate legal, political, administrative, financial, cultural and diplomatic conditions. Recognition in the literature and in practice of ‘transboundariness’ dates to the 1970s and has grown since. The authors trace the evolution of transboundary water scholarship and identify five framings used in transboundary water governance and management: conflict and cooperation; hydropolitics; hydrodiplomacy; scale; and disciplinary approaches. Transboundary water management initiatives can be viewed through three broad strands: interventions, advancements in governance strategies and democratization of data and information for strengthening science–policy interaction. The authors close with a discussion of future directions for transboundary water governance and management, emphasizing the need for additional research on how to deal with climate-related and other mounting challenges.
