BACKGROUND: Many arteriovenous malformations (AVMs) can be treated with one modality, but with increasing complexity a combination of techniques, including surgical excision, embolization, and radiosurgery, may be beneficial. The 2 senior authors' experience in the multimodal management of AVMs from 1980-2008 is reported, including the results in all patients with rehemorrhage while awaiting treatment or after partial initial treatment has begun. The series contains a disproportionately high number of Spetzler-Martin grade IV and V lesions, owing to the nature of the referral practice. METHODS: Data were collected prospectively. Only patients who were managed until treatment options were exhausted were included; this entailed either treatment to the point of AVM obliteration or inability to treat further using any or all modalities. Patients who presented with intracranial hemorrhage (ICH) in extremis in whom the AVM was excised during the first operation were also included. RESULTS: Of the 290 patients, 265 underwent treatment, and 25 were managed conservatively. An unruptured AVM was present in 48% of patients. Cure was achieved in 233 (88%) of treated patients. Cure was achieved in 25 of 37 patients undergoing radiosurgery only, 56 of 57 undergoing surgery, 100 of 101 undergoing embolization and microsurgical excision, 20 of 34 undergoing embolization alone, 12 of 17 undergoing embolization and radiosurgery, 5 of 5 undergoing surgery and radiosurgery, and 14 of 14 patients undergoing all 3 modalities. Spetzler-Martin grade was found to correlate negatively with cure (P < 0.001). There was a good outcome in 210 patients (72%), moderate disability in 40 patients (14%), severe disability in 22 patients (8%), vegetative state in 1 patient, and 17 patients (6%) died. There was a favorable outcome (no or only moderate deficits) in 93% of patients with Spetzler-Martin grade I-III lesions. The outcome was favorable in 13 of 25 patients (52%) having no treatment, 32 of 37 (86%) having radiosurgery only, 30 of 34 (88%) having embolization only, 54 of 57 (95%) having surgery only, 87 of 101 (86%) having embolization and surgery, 16 of 17 (94%) having embolization and radiosurgery, 5 of 5 (100%) having surgery and radiosurgery, and 13 of 14 (93%) having all 3 modalities. These outcomes included morbidity from initial presenting symptoms, from treatment, and from rehemorrhage. Good recovery was more likely in patients who were treated with surgery as one of the treatments (P = .025). Considering only new deficits related to treatment, 9 patients (3%) incurred severe neurologic deficits, 11 patents died after treatment, 2 patients died of postoperative hematomas, and 6 died of rehemorrhage from residual AVM. Increasing age, Spetzler-Martin grade, and rehemorrhage were correlated with a poorer Glasgow Outcome Scale score (P < 0.05). CONCLUSIONS: These data suggest a higher risk of hemorrhage after partial obliteration of AVM. One should ascertain an acceptably high likelihood of complete obliteration before embarking on treatment. Using a multimodality approach, the authors were able to cure 92% of treated Spetzler-Martin grade I-IV lesions but only 53% of treated Spetzler-Martin grade V lesions. A major neurologic deficit, disabling to the patient, was incurred in 3% of cases, and 11 patients died.