Since 1950 a number of new antihypertensive drugs have come into use and have helped to change not only our clinical management but also our basic concepts of essential hypertension. These drugs have in common only their antihypertensive property, and even this is mediated differently by eaeh of them. Thus the ganglionic blocking drugs reduce the activity of the sympathetic nervous system, the veratrum products stimulate the depressor activity of the parasympathetic nervous system, the Rauwolfia derivatives lessen the pressor effects of central nervous agitation, hydralazine dilates the arteriolar system, particularly in the kidney, and chlorothiazide augments natriuresis, and may decrease renal pressor activity. Each of these drugs has a place in the treatment of different patients, and several or even all of them may be used in combination in certain cases.