Innovative decision making for sustainable management of water aims at providing tools needed if any integrated and participatory management of water should be carried out. Management refers in this context to its core element, the decision making process (DMP). Focusing at water supply and sanitation (as there the need is paramount), DIM-SUM will carry out one case study in one river basin in each participating partner country: Indonesia, Maharashtra-India, Malaysia and Nepal in order to evaluate and develop these tools.