For over 100 years, water policy and man agement in Spain have been instruments of economic and social transformation. Sig nificant public and private investments in water supply infrastructures have equipped Spain with over 1,200 major dams, 20 major desalination plants ? with more under construction ? and several interbasin water transfers. The system has been apparently very successful, with an increase in overall water availability, strong associated eco nomic development and few urban water supply shortages. This success has been supported by a widespread consensus among a strong and largely closed water policy community made up of water manag ers, irrigators, electric (hydropower) utilities and developers