The experiments of Goldblatt1and others2who have shown that hypertension may be produced in dogs by partial constriction of the renal arteries by means of metal clamps have stimulated a more careful search for primary localized renal disease, particularly chronic pyelonephritis, in human beings with so-called essential hypertension. Although there is no evidence of chronic pyelonephritis in the majority of cases of essential hypertension, several investigators (Longcope,3Butler4and Weiss and Parker5) have felt that the association of these conditions was frequent enough to be more than incidental. Butler has reported a case in which hypertension was associated with unilateral chronic pyelonephritis in a child aged 7 years. Surgical removal of the affected kidney was followed by return of blood pressure to normal; the pressure had remained normal for twenty months at the time of Butler's report. Barney and Suby6have reported a