The incidence of Vibrio parahaemolyticus in products of the Malaysian export shrimp processing industry was investigated through the stages from the catch to that of the cooked, peeled and frozen product. The organism was commonly found in freshly caught and landed shrimp, and could be detected by enrichment culture at all stages of processing. The number of V. parahaemolyticus in shrimp varied from nil to 4x10(4), and 19 of the 50 serotypes in the current antigenic scheme were found, O1-K38 and O1-K32 occurring most often. All the isolates were Kanagawa-negative; one strain was a sucrose-positive variant. The study indicated that specifications of 10(2) g-1 for V. parahaemolyticus in raw tropical shellfish are too stringent but that the Malaysian shrimp industry should be able to meet this requirement for cooked shrimp.