Neurogenesis is known to occur in the specific niches of the adult mammalian brain, but whether germinal centers exist in the neural-crest-derived peripheral nervous system is unknown. We have discovered stem cells in the adult carotid body (CB), an oxygen-sensing organ of the sympathoadrenal lineage that grows in chronic hypoxemia. Production of new neuron-like CB glomus cells depends on a population of stem cells, which form multipotent and self-renewing colonies in vitro. Cell fate mapping experiments indicate that, unexpectedly, CB stem cells are the glia-like sustentacular cells and can be identified using glial markers. Remarkably, stem cell-derived glomus cells have the same complex chemosensory properties as mature in situ glomus cells. They are highly dopaminergic and produce glial cell line-derived neurotrophic factor. Thus, the mammalian CB is a neurogenic center with a recognizable physiological function in adult life. CB stem cells could be potentially useful for antiparkinsonian cell therapy.