In a previous paper1we presented the results of 350 consecutive cases of hypertension in which treatment was by bilateral supradiaphragmatic splanchnicectomy and lower dorsal sympathetic ganglionectomy. Our purpose in the present paper is to compare the results of this operation with those of an analogous series in which treatment was by medical means alone. The first 76 consecutive cases of our main series were chosen for this study because the postoperative period of from five to seven years seemed adequate to evaluate the results fully and because this time period lends itself to comparative study. A careful review of the literature concerning the results of therapy and the mortality rate in hypertension reveals an unexpected degree of confusion. This confusion results chiefly from inadequate classification of the cases before and after therapy and an inadequate period of observation after the therapy. The fundamental question in the mind of