Many of today’s most pressing problems can be described as problems of collective action, caused by actors’ increasing demand for free-access goods, such as clean air and water. This project contributes theoretically to one of the major political science puzzles– the mechanisms behind large-scale collective action problems, and how they can be overcome. We focus on a particularly challenging, and theoretically underdeveloped, type of collective action problem arising (a) when the resource moves across administrative boundariesand (b) when management efforts implies asymmetrical payoffsfor the actors involved, as the negative consequences of defective behaviour is more tangible for actors in one geographical location than in others. The main question is: To what extent, and by which mechanisms, is cooperation and coordination in upstream-downstream situations possible?The empirical study consists of survey experiments with politicians and citizens in municipalities along the Göta River in Sweden, a water system with evident upstream/downstream relations. We investigate what factors affect upstream and downstream actors’ willingness to set aside their short-term interests and cooperate in order to manage risks threatening the production of safe drinking water. Due to our focus on the highly pressing societal issue of safe water provision, the project contributes with important empirical knowledge on the conditions for sustainable water management.