With increasing global change pressures, and due to existing limitations, and un-sustainability factors and risks of conventional urban water management (UWM), cities experience difficulties in efficiently managing the ever scarcer water resources, their uses/services, and their after-use disposal, without creating environmental, social and/or economic damage. In order to meet these challenges, SWITCH calls for a paradigm shift in UWM. There is a need to convert ad-hoc actions (problem/incident driven) into a coherent and consolidated approach (sustainability driven). This calls for an IP Approach. Research concept SWITCH therefore proposes an action research project which has as a main objective: The development, application and demonstration of a range of tested scientific, technological and socio-economic solutions and approaches that contribute to the achievement of sustainable and effective UWM schemes in "The City of the future". The project will be implemented by different combinations of consortium partners, along the lines of seven complementary and interactive themes. The research approach is innovative for the combination of: action research: address problems through innovation based upon involvement of users. Learning alliances: to link up stakeholders to interact productively and to create win-win solutions along the water chain; multiple-way learning: European cities learn from each other and from developing countries, and vice versa. Multiple-level or integrated approach: to consider the urban water system and its components (city level) in relation to its impacts on, and dependency of, the natural environment in the river basin (river basin level), and in relation to Global Change pressures (global level). Instruments and scope: An IP with 30 partners, their resources, and a total budget of 25,191,396 EURO including budget for demonstration activities in 9 Cities in Europe and developing countries.