The book summarizes the results of the first Europe-wide Delphi study on future developments in the energy sector. With a time horizon of 2030, this expert survey not only provides a useful perspective on long-term developments of energy technologies, but also evaluates these technologies against different sets of social values or "visions". In the comprehensive analysis following the Delphi survey itself, special attention was given to faithfully translating the trends and needs identified by the survey participants into recommendations for R&D and energy policies. In this respect the EurEnDel findings provide a twofold contribution to the analysis of Europe's energy policies: - They corroborate the conflicting attitudes and paradigms prevalent among energy experts, with valuable new dimensions for the on going energy debate; - They offer genuine new insight on energy issues, with added value for decision makers.