The integrative trends that have been emerging in companies regarding IT, such as Single Point of Administration, require new concepts for authorization and authentication. This book provides a comprehensive presentation of role-based access concepts. Starting from the existing situation in companies and the historical derivation, it offers an overview of the authorization issues. The authors present practical and manageable concepts, providing both conceptual and generically technological solutions and evaluating them. A book for anyone professionally or academically involved with authorization procedures and access management.