The development of the Virtual Reality Modelling Language (VRML) for the Internet has resulted in the emergence of a multiplicity of 3D web sites. The metaphor used by these sites varies enormously from virtual galleries to virtual cities and style varies from abstract to reality. Additionally these worlds are populated by virtual objects, some having reactive or interactive properties, including movement, audio, video, databases, artificial intelligence etc. Perhaps the most stimulating embodiment of these new environments are those that offer the participant the opportunity to meet and communicate with other visitors exploring the same virtual space/world. The Glasgow Directory is an established 3D web space, with around 10,000 visitors per year. The model represents approximately 10,000 properties in the city and is populated by contextual information on its culture and socio-economic topography. This paper describes the background to this VR space, and suggests a set of design criteria for successfully deploying multi-user software within this and similar environments. These criteria take into account lessons learned by “observingi and analysing how participants interact with the existing system under different conditions and also what benefits they perceive on entering the environment via the multi-user interface. These recommendations will hopefully be applicable to a wide spectrum of internet virtual environment builders and users.