Clinical and genetic data of 10 patients with neurofibromatosis 2 (NF-2) are presented. Interestingly, no family history of neurofibromatosis was detectable in any of them, which indicates that these are sporadic cases of NF-2, most likely due to a new mutational event. According to our own results and the data in the literature, sporadic cases of NF-2 are clinically characterized by a high incidence of multiple meningiomas and spinal tumors in addition to the bilateral occurrence of acoustic neurinomas. The clinical heterogeneity of NF-2 is pointed out and the possible existence of different forms of this disease is discussed.