Economics for Energy and Instituto de Estudios Fiscales co-hosted a workshop in Madrid on 31 May 2011 to examine and debate the present and future of environmentally-related energy taxation in Spain. NERA Director Oscar Arnedillo delivered a presentation analyzing the motivation behind such taxes in Spain as well the likely environmental impact. Other session topics in the workshop included design principles of energy-environmental taxes, and an analysis of the role of the Spanish central government vs. the autonomous communities in the design and application of those taxes.