The decrease in water resources is one of the major preoccupations of international institutions in the present context. In several parts of the world, such as the Mediterranean area, over-exploitation of water is the result of easy availability and minimal investment costs but it causes serious damage to wetland ecosystems. Agricultural and environmental policies incoporating water management problems must therefore be developed. The case of the wetlands in the 'Tablas de Daimiel' national park in Spain, deteriorated by the over-use of water in irrigated farming, is examined here. The author makes a number of reflections concerning the new context of the European Union development policy and also analyses the profitability of the political options in which it is attempted to integrate environmental and economic objectives.