Brachial plexus neoplasms are uncommon. When this diagnosis is suspected, the functional and anatomical integrity of the brachial plexus and cervical spinal cord must be carefully assessed. A thorough search for other signs of neurofibromatosis (von Recklinghausen's disease) must also be completed. The distinction between neurilemoma and neurofibroma is an important and useful one to know. Evaluation by a pathologist who is well versed in neural tumors is mandatory for appropriate treatment of these usually benign lesions. Surgical intervention, adequately prepared on the basis of the patient's age, the amount of neural impairment, and the extent and histology of the tumor requires a surgeon who is experienced in peripheral nerve surgery and in microdissection techniques. Long-term follow-up is necessary to monitor the growth of known tumors, the detection of malignant change, and the appearance of other stigmata of von Recklinghausen's disease.