Introduction

We need to improve interaction and collaboration in immersive virtual environments. Indeed, frameworks for the design of immersive and collaborative virtual environments are now mature enough to allow researchers to focus on higher-level description of immersion and collaboration rather than on low-level system features. However, we still have to improve both the immersion of the users and the ability of distant users to collaborate efficiently when they are sharing a virtual environment, by proposing new metaphors for immersive 3D collaborative interactions.