Four regions stand out in terms of high climatic constraints, groundwater use, relatively lower availability of surface water, competition with other uses and externalities (but with differences in aquifer characteristics): the Mexican Region Laguna, Israel's Western Galilee, the US MPW region, and the Australian Murray-Darling Basin. A second group of regions in Japan, Korea, Denmark, France, Portugal, Spain and the Netherlands do not rank as high in many of these categories with relatively more available surface water, less arid current and projected climate, lower level of groundwater use and externalities (with the exception of Spain's Mancha Occidental). Lastly, the Italian Campania region and the NHPA, SHPA and MAA regions in the United States appear to be intermediate in these dimensions. Regions differ in aquifer characteristics, but there is no simple pattern. Israel's Western Galilee and Mexico's Region Laguna both stand out again in terms of their relative emphasis on supply-driven approaches.