Until recently a neglected disease syndrome, diarrhea is responsible for many millions of infant deaths in developing countries. The result of a 1987 symposium, this volume reflects advances in the aetiology of diarrhea while addressing such puzzling problems as the difficulty of growing viruses in a controlled setting. The volume is deliberately restricted to so-called ``novel' diarrhea viruses and is not concerned with ``classical' rotaviruses, which have formed the basis of previous symposia. Articles concentrate on: atypical rotaviruses; the enteric adenoviruses; small round viruses such as astroviruses, caliciviruses and Norwalk virus; and the Berne and Breda viruses, suggested as a new family Toroviridae. The contributions come from an interdisciplinary mix of virologists (both human and veterinary), epidemiologists, molecular biologists, and pathologists.