Many new services have emerged to realize ubiquitous computing environments, owing to the increasing supply of mobile devices and more widespread Internet and wireless network facilities. This paper introduces the U-Campus (Ubiquitous computing for Campus) service. This study has been conducted through interdisciplinary research by four participating departments. The U-Campus Project is part of the UTOPIA project (Ubiquitous computing TOwn Project: Intelligent context Awareness), which covers town- and city-wide environments. Currently, a test bed for U-Campus has been constructed to support various services such as U-Profile, U-Messaging and U-Campus Tour Guide services. Students, professors, school staffs, and campus visitors can easily access the various available campus services by using image-based sensors and mobile devices such as CDMA cellular phones or WiFi smart phones. The major purpose of this research is to provide a context-aware U-Campus environment to users by utilizing sensors and mobile devices currently available in the public sector and the marketplace.