Neurofibromatosis (NF) comprises two distinct genetic disorders-neurofibromatosis type 1 and 2 (NF1 and NF2)-in which affected individuals develop both benign and malignant tumours. NF1 results from germline mutations in the NF1 gene that encodes neurofibromin, while NF2 results from germline mutations in the NF2 gene that encodes merlin (or schwannomin). The major tumour types arising in individuals with NF1 include neurofibromas, malignant peripheral nerve sheath tumours, and gliomas, whereas NF2 is characterized by the formation of schwannomas, meningiomas, and ependymomas. With the identification of the NF1 and NF2 genes and the generation of robust preclinical mouse models of NF-associated neoplasms, novel treatments that specifically target the growth control pathways deregulated in these tumours have been discovered, some of which are now being tested in clinical trials in individuals with NF1 and NF2. In this Review, we will highlight the key clinical features of NF1 and NF2 and the advances in future clinical management based on an improved understanding of the function of the NF1 and NF2 genes and the development of small-animal models.