Water is the common thread that links all aspects of human development. Water security is therefore vital to all social and economic sectors as well as the natural resource base on which the world depends. But an expanding population, growing economies and poor water management are putting unprecedented pressure on our freshwater resources. We simply cannot continue to use water as wastefully as we have in the past; we have to change the way we manage our water resources. scientists and policy makers have a joint responsibility to work together in the development of more sustainable solutions to existing and emerging water problems. this policy brief aims to highlight the integrated and coordinated nature of the response needed to fully incorporate water into the new green economies of the world.