Since its inception in 1996, FSR, the biannual "International Conference on Field and Service Robotics" has published archival volumes of high reference value. This unique collection is the post-conference proceedings of the 4^th FSR in Lake Yamanaka, Japan at July 2003. This book edited by Shin'ichi Yuta, Hajime Asama, Sebastian Thrun, Erwin Prassler and Takashi Tsubouchi is rich by topics and authoritative contributors and presents the current developments and new directions in field and service robotics. The contents of these contributions represent a cross-section of the current state of robotics research from one particular aspect: field and service applications, and how they reflect on the theoretical basis of subsequent developments. Pursuing technologies aimed at realizing skilful, smart, reliable, robust field and service robots is the big challenge running throughout this focused collection.