We describe a virtual reality widget library and two medical applications. These applications, built on the widget library, make use of collaborative interaction techniques. These techniques support a high degree of precision with respect to manipulation of data and data parameters. The 3D widgets are synchronized between collaborating clients in order to facilitate the high degree of interactivity necessary for productive investigation of shared medical models and data.

We discuss in detail the different challenges which face the investigator in an immersive 3D environment as opposed to that of a 2D desktop environment and how these differences have lead us to the criterion used for the development of the shared 3D Virtual Reality (VR) graphical user interfaces (GUIs) used in the biomedical applications presented.