A study of the presently available roentgenographic methods of opacifying the renal arteries has led us to the conclusion that percutaneous retrograde femoral catheter arteriography is the only complete and precise procedure. The relative hazards and technical problems encountered with other technics are a matter of general knowledge. Our interest lies simply in defining the limitations of the intravenous and translumbar needle artériographie , particularly in the light of the ease and greater diagnostic value of the newer percutaneous method. The following is a case presentation in which this point is illustrated: E. B., a 44-year-old Negro woman, was admitted to St. Luke's Hospital for the fourth time in June 1960, complaining of increasing blurring of vision and weakness. She was known to have had hypertension since 1955, although she had been asymptomatic until 1958, when headaches and visual disturbances developed. Her admissions to St. Luke's Hospital had begun early in 1959, when she was seen for progressive complications of her disease, including congestive heart failure, 4+ hypertensive retinopathy, weakness, and blurred vision. Blood pressures were in the range of 210/115. On her earlier admissions, laboratory tests demonstrated albuminuria with no formed elements and several negative urine cultures; blood urea nitrogen 12.3 mg. per 100 c.c. ; creatinine 0.8 mg. per 100 c.c; normal electrolytes; phenolsulfonephthalein excretion 53 per cent in one hour, 21 per cent in the first fifteen minutes. The Regitine test was negative. Differential salt excretion studies showed equal concentrations bilaterally, in the normal range. An intravenous urogram demonstrated minimal caliectasis on the right. This was verified by retrograde pyelography. The blood pressure and symptoms failed to respond to the usual medical regimen and consequently a sympathectomy was contemplated. Before this procedure was carried out, however, it was felt proper to exclude any correctable renal vascular disease. In January 1960, therefore, intravenous aortography was performed but failed to delineate the renal arteries adequately, although the aorta and its peripheral branches were well opacified (Fig. 1, A). This procedure was followed by a translumbar aortic puncture with excellent visualization of the right renal artery but poor demonstration of the left (Fig. 1, B). It was not possible to exclude surgically correctable structural alterations of these vessels on the basis of either of these two diagnostic studies. On readmission June 1960, a normal renal arterial structure bilaterally was demonstrated (Fig. 1, C) after percutaneous retrograde aortic catheterization. The demonstration of structural changes in the renal arteries in selected hypertensive patients is at the present time an accepted clinical step in determining possible etiology and in the selection of candidates for surgery.