Fifty patients (25 Blacks and 25 Indians) suffering from mild-to-moderate hypertension (supine diastolic blood pressure 100 - 105 mmHg) were studied in order to compare the antihypertensive effect of a combination of a beta-blocker (sotalol hydrochloride 160 mg/d) plus a thiazide derivative (hydrochlorothiazide 25 mg/d) ( Sotazide ; B-M) with that of a combination of reserpine 0,1 mg/d ( Serpasil ; Ciba) plus hydrochlorothiazide 25 mg/d ( Dichlotride ; Frosst MSD). The combination of reserpine plus hydrochlorothiazide was found to be as effective as that of sotalol plus hydrochlorothiazide in lowering the blood pressure in both the Black and the Indian patients. Two patients taking the combination containing reserpine developed side-effects, but this did not occur in any of those taking the combination containing sotalol. We feel that in developing countries, where the cost of therapy is important, reserpine in a dosage of less than 0,1 mg/d plus a thiazide derivative in low dosage is preferable to a beta-blocker plus a thiazide derivative in the treatment of hypertension.