Abstract
Ten irrigation systems in Nepal are analysed in order to find out how cooperation among users is related to incentives and coordination. The study combines statistical analysis with case studies of five of the irrigation systems. The data contain information for a wide range of variables over a long period of time and gives a direct measure of cooperation. I find that cooperation is best explained by a combination of incentive- and coordination related variables. The most striking result is the importance of personal leadership. The income level and the share of users belonging to the largest ethnic group are also positively correlated with cooperation. Income inequality and, more surprisingly, the existence of a water users' association, are negatively correlated with cooperation. Cooperation was also lower during the first years of democracy. Neither the age of the system, the number of users or the ethnic heterogeneity of the users seemed to be of any considerable importance for cooperation.