Neuronal stem cells are like other tissue-specific stem cells, undifferentiated cells which can proliferate and may give rise to glia and neurons. They are present in mammalians throughout the entire life and are supposed to play an important role in renewal of neurons. However, little is known about the origin, phenotypic expression and function of neuronal stem cells in the adult brain. In the present review the occurrence and origin of neuronal stem cells as well as specific markers, which allow their identification in the brain is being described. Finally the role of these cells in the adult brain and their potential use in neuropathy is discussed.