Starting from case studies, the authors develop a methodical representation of intelligent software agents. After laying the foundations they give a comprehensive description of the basic building blocks of agents and agent systems. These include in particular the architectural possibilities for constructing intelligent software agents and cooperation and communication in multiagent systems. Following the discussion of relevant development methods and tools, the application areas for intelligent software agents are explained. In numerous examples the reader will find extensive descriptions of individual software agents, among others the agents Firefly and Kasbah. Equal importance is attached to both the basic building blocks and the practical implementation of intelligent software agents. The book is equally suitable for both users and developers.