Abstract The brain is supplied by the branches of two internal carotid arteries (ICA) and two vertebral arteries. The terminal branches of ICAs and vertebral arteries form the circle of Willis to provide uninterrupted circulation. Branches of ICAs are the ophthalmic, posterior communicating, anterior choroidal, anterior cerebra,l and middle cerebral arteries. Branches of vertebral arteries are the anterior and posterior spinal arteries, and posterior inferior cerebellar arteries. Both the vertebral arteries merge to make the basilar artery. Acute occlusion of these arteries causes various type of stroke syndromes. Venous drainage of the brain is through superficial and deep cerebral veins. Both superficial and deep cerebral veins drain into various dural venous sinuses to eventually drain to brachiocephalic veins to the right atrium.