STAPHYLOCOCCAL food poisoning is overwhelmingly the most prevalent of foodborne infections in the United States. The need for improved methods of controlling the disease is indicated by the number of outbreaks reported in the annual summaries of disease outbreaks, which show little evidence of decrease in incidence (1-4). Factors responsible for outbreaks of staphylococcal food poisoning have not been clearly defined. It is difficult, if not impossible, to determine those conditions required to render food poisonous because no satisfactory laboratory test has been found for the presence of staphylococcus enterotoxin in food (5-7). At present, the only means of clarifying these factors appears to be through analysis of unselected outbreaks of this disease. Ninety-five outbreaks of staphylococcal food poisoning in 1955 and 1956, reported in the weekly communicable disease summaries issued by the Public Health Service, were surveyed. More complete data on 89 of them were obtained from the State, county, and city health officers reporting the incidents.