This important new work offers a comprehensive and compelling account of State aid law and policy and its application to the energy sector. Clearly structured and offering meticulous detail and robust analysis, it is required reading for all practitioners in the field. The volume explores general questions from the definition of State aid to its application in Member States by national courts. It also examines questions of procedure, questions of compatibility, and State aid and the EEA. It is an invaluable tool for lawyers, policymakers and tax professionals specialising in State aid law and energy law, written by a team of leading practitioners and academics in the field.