Africa's human population is growing rapidly and is set to account for 40 percent of global numbers by 2100. Further development of its inland waters, to enhance water and energy security, is inevitable. Will it follow the development pathway of industrialized countries, often destructive of ecosystems, biodiversity, and river-dependent social structures, or can it chart a new way into the future based on global lessons of equity and sustainability? This essay tracks the global and African growth of the benefits and costs of water resource developments, explores the reasons for the costs, and offers insights on new scientific thinking that can help guide Africa to a more sustainable future.