A review was performed of 114 patients with symptoms of vertebrobasilar insufficiency (VBI) alone, or in combination with carotid territory transient ischemic attacks or carotid territory completed stroke (cCS) with follow-up extending to ten years. The most frequent symptoms of VBI were visual changes (50%), dizziness (31%), and syncope (30%). Patients with symptoms of VBI and arteriographic evidence of intracranial disease, regardless of stump pressure, are at high risk for cerebral ischemia during endarterectomy. At late follow-up, ranging from one to ten years, 63% of the patients were alive; 88% were asymptomatic. Causes of death were mainly cardiac (44%) and stroke (36%), but patients with symptoms of VBI and cCS died earlier and from a second cerebrovascular accident. When a correct preoperative diagnosis was established, carotid endarterectomy produced relief of symptoms in 90% of the patients.