The emergence of magnetic resonance imaging with gadolinium has dramatically enhanced our ability to accurately detect the presence of acoustic tumors as small as 2 mm in diameter. Early diagnosis and improved surgical techniques continue to reduce the morbidity associated with surgical removal of these lesions. There exists, however, a select group of patients in whom no treatment may be the most appropriate management. Since 1979, a total of 51 patients with radiographic evidence of an acoustic neuroma have been prospectively followed for tumor growth and progression of symptoms. Patients were chosen for this conservative approach on the basis of age, medical condition, tumor size, audiometric data, and patient preference. This study reveals that a significant number of patients with acoustic tumors can be safely followed with regular imaging studies and may never require treatment. Discussed are tumor growth rates, epidemiology, and the impact of these factors on patient management.