Sustainability is a new, important discourse aimed at promoting a new strategy in the development of energy, water and environmental (EWE) systems -- the key components that affect the quality of life on our planet. It is becoming increasingly clear that the quest for sustainable development requires integrating economic, social, cultural, political and ecological factors. The behavior and properties of an EWE system arise not merely from the properties of its component elements, but also to a large degree also from the nature and intensity of their dynamic interlinkages. This volume helps clarify the complexity of these problems by providing a deeper understanding of the implications of the different aspects of sustainability.This work contains a collection of selected, peer-reviewed and state-of-the-art reflecting papers that were presented at the Third Dubrovnik Conference on Sustainable Development of Energy, Water and Environment Systems that was held in June 5-10, 2005 in Dubrovnik, Croatia.