This book is the third official archival publication devoted to RoboCup and documents the achievements presented at the Third Robot World Cup Soccer Games and Conferences, Robo-Cup-99, held in Stockholm, Sweden in July/August 1999. The book presents the following parts- Introductory overview and survey- Research papers of the champion teams and scientific award winners- Technical papers presented at the RoboCup-99 Workshop- Team description of a large number of participating teams.This book is mandatory reading for the rapidly growing RoboCup community as well as a valuable source or reference and inspiration for R&D professionals interested in multi-agent systems, distributed artificial intelligence, and intelligent robotics.