The protection of legitimate expectations appears to be a key concept of administrative law in Europe; it defines the legal position of the individual vis-à-vis the public authorities and is, thus, a gateway for constitutional considerations in administrative law.This book presents the results of a comparative research project dealing with the question if, to what extent, and in which ways the legitimate expectations of private parties are considered in procedures leading to a primary administrative decision and, where available, in subsequent review procedures before administrative, judicial or quasi-judicial bodies. Furthermore, the project examines if, and to what extent, European and national legal orders, as well as international legal regimes, guarantee compensation in cases where provisions concerning the protection of legitimate expectations have been disregarded.The contributions to the book, including surveys of the theoretical and philosophical background, country reports and comparative analyses, are written by scholars from 16 European countries, giving an insight into the various legal systems, their understanding of, and their methods of interpreting and applying, administrative law.