America’s fragmented water sector is unsustainable, with tens of thousands of utilities operating nearly 50,000 community water systems. Most of these water utilities lack the technical, managerial, and financial capacity to operate efficiently and effectively. Sweeping consolidation is the clear solution. Congress recognized the need for consolidation when it passed the Safe Drinking Water Act (SDWA) in 1974; water sector leaders repeated the call for consolidation on the law’s 25th anniversary in 1999. Yet the drinking water industry remains highly fragmented 25 years later. Consolidation will not solve all of the nation’s drinking water problems, but without significant consolidation no other reform is likely to work in the long run. How much to consolidate is not as clear. How big is big enough? This chapter analyzes data on SDWA compliance, utility performance, and operational efficiency to identify a scale of consolidation that offers the best chance at sustainable excellence. A remarkably consistent picture emerges: the greatest potential improvements from consolidation are achieved when utilities serve around 20,000 or more customer connections. Taken together, these results suggest that consolidating the American drinking water sector to about 6,000 utilities with a minimum size of 20,000 connections would deliver better health, greater efficiency, more effective regulation, and lower prices.