The clinical course, operative technique, and angiographic outcome are reported for a patient with a giant intracranial aneurysm of the proximal middle cerebral artery (MCA) who presented with symptoms of ischemia. Treatment of the aneurysm required bypassing the involved MCA bifurcation, but the patient lacked a suitable donor superficial temporal artery. The involved arterial segment was therefore bypassed with a side-to-side anastomosis of the anterior temporal artery to one of the secondary trunks of the MCA. This bypass eliminated the need to harvest a vein graft and re-established flow using in situ intracranial vessels of similar diameter, minimal arterial dissection, and only one suture line.