Telepresence is enabling human interaction at a distance, creating a sense of being present at a remote location. In practice, telepresence systems utilize a very wide range of technologies. In compiling this book, the editors have included chapters from across these technologies which they have broadly classified as audio, data, video and virtual environments. This book gives a flavour of the developments in telepresence and teleconferencing technologies being researched and developed within BT. It is useful reading for researchers, engineers and managers working in this field.