This book provides clear guidance on what constitutes State Aid in the area of tax law. It clearly explains the situations in which beneficial tax provisions for the taxpayer--e.g., lower tax rates for certain industries or for certain economic zones, advantageous depreciation rules, or exemptions --can be declared void by the European Commission. The difficult controlling concept of selectivity of an aid is dealt with extensively. Drawing on familiarity with the practice of the Commission, as well as the jurisprudence of the General Court and of the Court of Justice, thirteen knowledgeable contributors present valuable arguments in case the Commission requires the repayment of advantages received. Among the topics and issues covered are the Complete with case studies and analyses of the latest case law on selectivity, this invaluable resource will be welcomed by practitioners who, although they may be well-versed in tax law, are sure to benefit greatly from the authors' expert guidance on State Aid provisions and the rules on harmful tax competition.