Twenty-seven patients with mild to moderate essential hypertension were randomly assigned to receive 5 mg of ramipril once daily or 250 mg of methyldopa twice daily for eight weeks. Similar reductions in diastolic blood pressure and heart rate were noted in the two treatment groups during treatment. Perhaps because of the limited number of patients, no between-group differences in the results of a measure of quality of life were found, but on overall assessments of treatment outcome by patients and the investigator, slightly better outcome was apparent in the ramipril-treated patients. No side effects or clinically significant changes in laboratory test results were reported. It is concluded that ramipril is a safe and effective agent in mild to moderate hypertension when administered as a single daily dose.