Global water issues are likely to be as important in the foreseeable future as the oil crisis was in the 1970s. As a result, there is an urgent need for management to be appraised of scientific work and of the uncertainties that are associated with it, and for scientists to be able to transmit their work in a comprehensible way. This text explores the management of water quality in urban, rural, and coastal environments. It brings together science and policy making.