Water, energy and food are key resources to sustain life, and are the fundamental to national, regional and global economies. These three resources are interlinked in multiple ways, and the term "nexus" captures the interconnections. The nexus has been discussed, debated, researched, and advocated widely but the focus is often on the pairings of "water-energy" or "water-food" or "energy-food." To really benefit from the nexus approach in terms of resource use efficiency it is essential to understand, operationalize and practice the nexus of all three resources. As demand for these...