Over twenty people became ill with salmonellosis following a meal at La Tapatia Mexican restaurant in South San Francisco, San Mateo County. The restaurant was pinpointed as the source of the outbreak after careful investigation by health department officials. The specific strain of Salmonella Enteritidis isolated from case-patient stool samples matched those found in an outbreak involving raw almonds (phage type 30, PT30) that had occurred in California in year 2000; La Tapatia had used raw almonds in some of the dishes, however, no salmonella was ever isolated from the almonds sampled at La Tapatia. Cases were more likely than controls to have eaten fresh salsa. Tomatoes and cilantro were ingredients in the fresh salsa. Tomatoes that were supplied to the restaurant were of the same tomato source that were later linked to other Salmonella Enteritidis PT30 cases.