Twelve people developed gastrointestinal symptoms suggestive of food poisoning after a party attended by between 60 and 80 people. The outbreak went unrecognised, however, until general practitioners admitted three patients to hospital, where faecal specimens were examined. An epidemiological investigation identified 12 cases, and a case control study showed a significant association between illness and eating a cheese and onion quiche at the party. Salmonella enteritidis phage type 4 was cultured from three out of seven faecal specimens obtained from cases. Consultants in communicable disease control should continue to encourage general practitioners to investigate and notify suspected cases of food poisoning.