location and growth pattern of these tumors. The preoperative considerations, operating room set-up, patient positioning, and neuronavigational equipment are described for microsurgery in the cerebellopontine angle region. The operative techniques for removing acoustic neurinomas in correlation with size and extension of the tumor are then provided in step-by-step detail; intraoperative photographs are paired with explanatory colored line drawings of astonishing clarity. Finally, the tumors of the cerebellopontine angle that may mimic acoustic neurinoma are described.