This paper re-establishes the theoretical framework for participatory design evolved in the late sixties and early seventies as part of the movement towards a more explicit design methodology and attempts an explanation of why the concept failed to gain commitment from the architectural and urban design professionals. The issue of user participation in the processes of building and urban design is enjoying renewed attention following its relative neglect over the last 20 years due, in large measure, to significant advances in emerging information technologies, particularly multimedia, virtual reality and internettechnologies. This paper then gives an account of two significant and relevant developments in the evolution of the application of informationtechnologies with which the authors have been engaged. These are:a responsive and interactive interface to wholly immersive and realistic virtual reality representations of proposed buildings and urban neighbourhoods. an intuitive and platform-independent VR modelling environment allowing collaborative evolution of the scheme from withinthe virtual world. The efficacy of these IT developments is tested in the context of a design exercise in which three designers, from distributedlocations and using different computer platforms, collaboratively design an Information Centre from within the virtual world.