A combined epidemiologic, clinical, and electroencephalographic study of epilepsy was undertaken in Bogota by the Neurological Institute of Colombia, the Colombian Institute of Health, and the Department of Health of the City of Bogota. The prevalence of epilepsy on December 31, 1974, was 19.5 per 1,000, the highest rate for general populations reported in the literature. The prevalence was significantly higher for females than for males, 22.9 per 1,000 compared with 15.5 per 1,000.