A review of 50 hospital-based outbreaks of food poisoning which were reported in Scotland during 1973--7, is described. At least 1530 persons consuming hospital-prepared food were involved. Thirty-one episodes were associated with Clostridium perfringens (C. welchii), 11 were due to food-borne salmonella infection, three to enterotoxigenic Staphylococcus aureus, and five incidents were of undetermined aetiology. This differs noticeably from the experience in England and Wales where salmonellas appear to predominate as the main cause of hospital outbreaks. Twenty-two incidents occurred in hospitals for psychiatric or mentally subnormal patients, and ten others were located in geriatric units. Only 33 hospitals were involved in the 50 outbreaks as nine hospitals experienced two or more episodes. The role of the hospital in the occurrence of food poisoning may be over-emphasized in comparison with other catering establishments, as outbreaks are more readily recognized and laboratory facilities are usually available for investigation, but it is also believed that many episodes may not be reported. The peculiar problems of the hospital-catering service and particularly those of the older long-stay hospitals, are discussed in relation to preventive measures which would minimize the hazards of food poisoning.