A programme of integrated technical research and development and cognitive and perceptual evaluation is underway, funded by the OU and EPSRC. This is directed towards realising comprehensive, computer generated, 3D audio environments. The target application areas are enhanced HCI for people with a visual impairment and educational audio virtual environments. The work is currently focused at eliciting the key technical and perceptual issues that impinge on the practical implementation of audio virtual environments within an educational context.