This book constitutes the refereed proceedings of the Third International Conference on Ubiquitous Intelligence and Computing, UIC 2006, held in Wuhan, China in September 2006. The 117 revised full papers presented together with a keynote paper were carefully reviewed and selected from 382 submissions. The papers are organized in topical sections on smart objects and embedded systems; smart spaces, environments, and platforms; ad-hoc and intelligent networks; sensor networks; pervasive communications and mobile systems; context-aware computing and systems; security, safety, and privacy; and services, models, and personal and social factors.