Dilatation of stenosis at the origin of the vertebral artery, using a Grüntzig balloon catheter, was attempted in 5 selected patients and was successful in 4. Two patients had isolated vertebral artery disease without significant carotid occlusive disease, while the other 3 also had ulcerated carotid plaques. All patients had classical vertebral basilar insufficiency and were being considered for reconstructive surgery; however, dilatation alleviated the symptoms and made surgery unnecessary. No complications were encountered. At 1-18 months, all patients remain free of symptoms. Percutaneous transluminal angioplasty is a feasible means of treating stenosis of the origin of the vertebral artery in carefully selected cases.