F IBROMUSCULAR hyperplasia (FMH), as a cause of renal artery stenosis and consequent renovascular hypertension due to ischemia of one or both kidneys, first became recognized as a pathological entity in 1938, 4 although the majority of reports have appeared only recently3 ,3,5,8,1~ By 1965, six patients were reported with a combination of the renal artery abnormality and intracranial aneurysms, none of which had apparently been responsible for a subarachnoid hemorrhage? The purpose of this paper is threefold: first, to call attention to the coexistence of intracranial aneurysms in a high percentage of patients with FMH of the renal arteries; second, to present yet another patient with FMH who, following renal artery surgery, developed a subarachnoid hemorrhage due to a middle cerebral artery aneurysm, for which she underwent craniotomy and clipping of the aneurysm, with recovery; and third, to comment on two other angiographic discoveries in this patient, stationary waves of one internal carotid artery and a fusiform splenic artery aneurysm.