Three years ago, two of us (H. P. W. and N. M. K.)1 reported a series of cases of characteristic retinitis associated with marked hypertension and adequate renal function. The history and clinical data differed from those usually noted in cases of chronic nephritis. We then pointed out the serious prognostic import of this typical retinitis. The term "malignant hypertension" was applied to this clinical condition, apparently correctly, because in all of the fourteen cases so diagnosed, death occurred within from one to forty-four months. Since then we have seen a large number of similar cases, in some of which moderate renal insufficiency had developed. In the present communication, we wish to present the observations in eighty-one cases. Forms of severe hypertension without this retinal picture, while recognized as potentially malignant, are not included in this series. Further data have been collected which show that this condition may occur even