This book constitutes the refereed proceedings of the 4th International Conference on Pervasive Computing, PERVASIVE 2006, held in Dublin, Ireland, in May 2006.

The 24 revised full papers presented were carefully reviewed and selected from 178 submissions. The papers are organized in topical sections on activity recognition, location, sensors, sensor processing and platforms, toolkits and gaming, security, pointing, interaction and displays, and smart homes, and beyond.