The authors report a series of 30 patients who underwent reconstruction of the internal carotid artery (ICA) at the skull base with the saphenous vein during the surgical management of lesions at the cranial base. This group represents about 9% of the total patients in whom the ICA in the cavernous or petrous segment was manipulated either during the surgical approach or dissection from the tumor. Two of these patients failed a clinical balloon test occlusion of the ICA, and, in 9 patients, cerebral blood flow during balloon test occlusion dropped to between 15 to 30 ml/100g/min. The patency rate is 86% over a mean follow-up time of 18 months. Of the 4 patients with graft occlusion, 3 were asymptomatic. The fourth patient who suffered ICA dissection with graft occlusion subsequently died from a massive cerebral infarction. Three patients with inadequate collateral circulation sustained minor strokes as the result of the temporary ICA occlusion during the grafting, but all are capable of leading independent lives. Two patients suffered acute graft occlusion within 12 hours of the surgery and underwent successful revision of the graft. None of the grafted patients suffered delayed occlusion or ischemic or embolic problems. The patients with malignant tumors died within 2 years of the operation from the original disease; total tumor removal was accomplished in 14 of the 19 patients with benign tumors. The aneurysms were successfully eliminated in all 5 patients. The lessons learned from this experience are discussed.