Abstract: Blister aneurysms are a rare cause of subarachnoid hemorrhage. They are easily overlooked on conventional imaging and catheter angiography due to their small size and unusual anatomic location. Whereas the medical management of subarachnoid hemorrhage is similar to that of saccular aneurysms, the surgical management of blister aneurysms is more challenging due to their unique pathology and higher risk of intraoperative rupture. Special consideration should be made for open management such as preparation of the option of bypass or the emerging use of endovascular techniques such as flow diversion. This chapter reviews the diagnosis and medical and surgical management of blister aneurysms.