Preface This book aims to offer a framework of administrative law from a non-national perspective, which looks at the foundations of the discipline regardless of its anchorage to a specific State experience. The idea stems from the desire to help students who deal with the legal phenomenon from a transnational point of view to understand administrative law through the analysis of problems and issues that occur with significant frequency in most national and ultra-national administrative systems, without privileging the narration of one or more legal systems in particular. The existence of unilateral and authoritative powers of public authorities, the way in which these powers come into conflict with the rights of citizens, the procedural rules governing the action of administrations and the review exercised by the judge over public decisions are, in fact, some of the constants of the doctrinal reflections of each administrative law system, both if one looks at legal orders with a long-standing tradition (consider France and Germany), and if one considers States or organizations, also global or supranational (consider China or the European Union), in which an accomplished administrative system is a more recent conquest. The present book shall therefore try to identify some fundamental questions, in order to provide guidelines and discuss solutions: the goal is not that of systematically analyzing a plurality of different administrative law systems or of comparing them with one another, but that of ascertaining the existence, regardless of the inevitable differences, of a common core that supports all of them.