The results of a prospective assessment of antiepileptic drug treatment carried out over a 12-month period, in the context of existing community health care in a rural area of a developing country (a highland region of northern Ecuador), are reported. A house to house survey defined all patients in the area with a history of epileptic seizures, and 192 patients with active epilepsy were recruited into the programme. These patients were randomised to treatment with carbamazepine or phenobarbital, and 139 completed the assessment. Treatment was carried out by health visitors and rural doctors, monitored by a team of neurologists, and standard treatment regimens were used. Treatment was effective in controlling seizures, 53% of the patients were rendered entirely seizure free in the second 6 months of therapy, and a further 14% had a 50% or more reduction in seizures. These results were similar to those reported in hospital based studies in developed countries. No significant differences were found between the efficacy and safety of phenobarbital or carbamazepine. Antiepileptic drug levels were monitored during the study, and ranges similar to those found in developed countries were recorded. Compliance was good. In view of the successful treatment in this community control programme, we would recommend that community programmes for the control of epilepsy in rural settings should be given a higher priority in the planning of health care provision than is commonly the case. Finally, the programme afforded the opportunity to study the efficacy of treatment in patients with chronic long-standing epilepsy, who had not been previously treated, and the results of this treatment were good.