Three cases of Wegener's granulomatosis with a classical course are described, 2 of which with fatal outcome in spite of immuno-suppressive therapy. Nephroangiography was performed during the oliguric or anuric phase. The appearances were similar to those encountered in glomerulonephritis and were compared with those in three cases of panarteritis nodosa. Two of these represented the classical form with intrarenal arterial aneurysms; the third was a case of the microscopic type presenting blurred intrarenal arteries with lumen variations and occlusions. These observations support the opinion that Wegener's granulomatosis nodosa are different diseases. Nephroangiography seems to be of value in their differentiation.