Data on the incidence of foodborne disease in 1981 are presented. A total of 415 incidents affecting 3618 ill persons was analyzed. In 122 incidents (1683 cases) the etiology was established: micro-organisms appeared to be the main causative agents. Clostridium perfringens was responsible for 18 of these incidents (106 cases), Staphylococcus aureus for 17 (67), Salmonella for 16 (1114), including the outbreak during the European Summit Conference at Maastricht (700 cases), Bacillus cereus for 15 (135) and Campylobacter jejuni for 13 (142). Two episodes were probably caused by Clostridium botulinum (2 cases) and ECHO-viruses (48). In 7 episodes (11 cases) illness resulted from ingestion of food contaminated with scombrotoxin, in 6 episodes (13) with saxitoxin (shellfish poison). In 16 incidents (32 cases) foods had been contaminated with chemical substances. Cases of foodborne disease recorded by the Chief Medical Inspectorate included infections from Salmonella (7496), C. jejuni (1496) and Yersinia enterocolitica (262). However, these could not be analyzed further due to a lack of epidemiological information. Meat and meat products (49 incidents), fish and shellfish (42), Dutch meals (42) and Chinese foods (128) were associated with outbreaks most frequently. About 60% of the incidents involved places where food is prepared for immediate consumption. Examples of outbreaks are presented.