Despite decades of critical analysis, the precise indications for cerebral revascularization remain poorly defined. It is clear that some patients undergoing therapeutic carotid artery (CA) sacrifice for the management of unclippable intracranial aneurysms or skull base neoplasms will require revascularization to prevent or reduce the risk of cerebral infarction. 4,11 Nevertheless, the decisions of when to perform this procedure and what type of bypass to undertake in these cases remain debated. The question of whether revascularization should be conducted in cases involving ischemic disease is even more controversial. 1–3,5,8 This issue of Neurosurgical Focus is devoted to the topic of cerebral revascularization, assembling a collection of articles from noted experts in this field. The papers address many of the challenging and important issues yet to be defined in this controversial area.