Ciguatoxic fish constitute a continuing foodborne disease problem in Miami. Information from 129 cases of ciguatera fish poisoning reported to the Dade County (Miami) department of Public Health during 1974 to 1976 was used for epidemiologic study of the syndrome. The case definition required that both gastrointestinal and paresthetic neurological symptoms be experienced within 36 hours after eating fish. Grouper and snapper were the fish most frequently implicated. Neither methods of storage nor means of preparation seemed to affect fish toxicity. A predominantly late spring and summer seasonality was noted. The true annual incidence of this syndrome in Miami may be ten times the number reported to the health department, suggesting an average annual incidence of at least five cases per 10,000 resident population. Recent advances in ciguatoxin research may lead to much needed assays for toxin detection.