Book excerpt: RoboCup is an international initiative devoted to advancing the state of the art in artificial intelligence and robotics. The ultimate, long range goal is to build a team of robot soccer players that can beat a human World Cup champion team.This is the first book devoted to RoboCup. It opens with an overview section presenting the history of this young initiative, motivation, the overall perspectives and challenges, and a survey of the state of the art in the area. The technical paper section presents the state of the art of the interdisciplinary research and development efforts in details, essentially building on the progress achieved during the RoboCup-97 Workshop. The team description contributions discuss technical and strategic aspects of the work of the participating teams.