One third of the world’s population lives in countries experiencing moderate to high water stress. This global water situation will get considerably worse over the next 30 years, as the share of the world’s population in countries undergoing water stress could rise to two thirds by 2025. Such a water shortage leads to competition between users. At the international level this means increased conflicts between nations that share water resources. For many countries water sets a ‘development ceiling’. It constrains improvements in: agriculture, industry (including travel and tourism) and home use.