In a prospective, multicenter study of 164 patients, cerebral magnetic resonance (MR) angiography with multiple overlapping thin slab acquisition was evaluated for image quality and diagnostic accuracy. Of the 164 patients, 87 (53%) underwent either correlative cut-film angiography or surgery. The overall image quality was excellent in 90% of patient studies. Eighteen of 19 aneurysms were detected with MR angiography. The parent artery, the anatomy of the neck and dome, and the size were correctly shown in 17 of the 19 aneurysms. All 19 vascular malformations were seen with MR angiography. Venous malformations and single pedicle arteriovenous malformations were completely defined with MR angiography, while complete definition of complex arteriovenous malformations was frequently difficult. In cerebral tumors, the arteries and veins important in surgical planning were accurately shown in all cases. In ischemic cerebrovascular disease, MR angiography depicted all stenoses and occlusions of first- and second-order cerebral arteries. The inability to depict intraluminal filling defects in any but the large central arteries limited the ability of MR angiography to enable the specific diagnosis of embolic stroke.