Neurofibromatosis type 1(NF1) is an autosomal dominant condition with a worldwide incidence of ∼ 1 per 2500 to 3000 individuals. Caused by a germ-line- inactivating mutation in the NF1 gene on chromosome 17, the disease is associated with increased morbidity and mortality. In the past several years, significant progress has been made in standardizing management of the major clinical features of neurofibromatosis type 1. Moreover, improved understanding of how the neurofibromatosis type 1 protein, neurofibromin, regulates cell growth recently provided insight into the pathogenesis of the disease and has led to the development of new therapies. In this review, we describe the clinical manifestations, recent molecular and genetic findings, and current and developing therapies for managing clinical problems associated with neurofibromatosis type 1. Copyright © 2009 by the American Academy of Pediatrics.