The Acheson Report expressed concern about doctors' knowledge of the infectious disease notification system. This study was undertaken in order to quantify doctors' knowledge of the system, and guide action to improve its efficiency. A survey of 176 hospital doctors in one large Health District showed that, although 82% knew of the legal obligation to notify, 70% did not know where to obtain a notification form, and 40% did not know whom to notify. Over a third of those surveyed did not know that food poisoning and tuberculosis are notifiable diseases. Proposed changes in the law relating to infectious disease control will not compensate for such lack of knowledge. Consultants in Communicable Disease Control should take the lead in improving this vital information system.