Table 3. Uncertainties in the Upper Guadiana Basin when multiple knowledge frames are considered Unpredictability (we don’t know and we will not know ...) Incomplete knowledge (we don’t know but we could get to know ...) Multiple knowledge frames (different actors give different answers to the question ...) Natural system How do the complex dynamics of groundwater processes affect the day-to-day water level? What are current piezometric levels? Is this an area of valuable wetland ecosystems disturbed by farming, or of valuable agricultural activities that need water? Technical system What are the side-effects of building a structure for water transfer? How much water can be saved with new irrigation technologies? Is the water-transfer system a tool for optimal water distribution in the country or is it an expensive infrastructure that favors provinces with more voters? Social system What would stakeholders’ reaction be to a stronger control of illegal extraction? How much water is taken from the ecosystem by illegal water extraction? What are the economic impacts of reducing the amount of illegal extraction? Is the main problem excessive water consumption, illegal water extraction, or insufficient water supply? Is the main problem lack of environmental awareness among famers or lack of law enforcement?