To evaluate complications and their prevention in endovascular treatment of dural arteriovenous fistulas (AVFs), we analyze the medical records of 105 patients (47 men 58 women, mean age of 64.2 years) treated with endovascular procedures from 1990 to 2003 in our clinic. Dural AVF was located at the cavernous sinus in 43 patients, transverse-sigmoid sinus in 43, and other regions in 19. There were 201 procedures, including 97 transarterial embolizations (TAE), 84 transvenous embolizations (TVE), 17 surgical TVEs, and 3 sinoplasties. Twelve complications were recorded in 10 patients (3 cavernous sinus, 5 transverse-sigmoid sinus, and 2 craniocervical junction lesions). The complications were divided into 4 categories: wrong strategy (1 case), venous thrombosis (2 cases), procedural error (7 cases), and general condition (1 case; pulmonary embolism). One of the superficial middle cerebral veins was obliterated after coiling of the cavernous sinus in 1 patient, resulting in a mild transient hemiparesis (wrong strategy). The syndrome of paradoxical worsening occurred in 1 patient with cavernous sinus dural AVF after TAE (venous thrombosis of the central retinal vein). One patient with sigmoid sinus dural AVF suffered long-lasting dizziness after TVE. Ipsilateral endolymphatic hydrops were observed and speculated to be a causative factor of the patient's dizziness (venous thrombosis of the inner ear). The procedural error included trigeminal nerve palsy due to excess coil packing (1 case in TVE), ischemic cranial neuropathy (3 cases in TAE), and migration of the embolic materials via the feeding arterial collateral network (3 cases in TAE). Morbidity and mortality were 4.8% and 1.0%, respectively. We discuss causes and preventive measures.