This Atlas summarizes current surgical strategy for cerebral revascularization in the treatment of complex neurovascular diseases. It focuses on complex intracranial aneurysms, which are mostly large/giant, irregular and short of enough collateral compensation. In the first part, it starts from the extracranial-intracranial (EC-IC) bypass strategy. For the complex middle cerebral artery aneurysms, the types of EC-IC bypass are determined based on the angioarchitecture. Furthermore, various intracranial-intracranial (IC-IC) bypasses are introduced, with the advantage of no need for graft vessel harvesting and preferable matching of donor and receipt arteries. This Atlas provides useful knowledge and cases about this basic and indispensable skill for neurosurgeons.