Hair follicle stem cells (HFSCs) normally give rise tokeratinocytes, sebocytes, and transient amplifyingprogenitor cells. Along with the capacity to proliferaterapidly, HFSCs provide the basis for establishing aputative source of stem cells for cell therapy. HFSCs aremultipotent stem cells originating from the bulge area.The importance of these cells arises from two importantcharacteristics, distinguishing them from all other adultstem cells. First, they are accessible and proliferate forlong periods. Second, they are multipotent, possessingthe ability to differentiate into mesodermal andectodermal cell types. In addition to a developmentalcapacity in vitro , HFSCs display an ability to formdifferentiated cells in vivo . During the last two decades,numerous studies have led to the development of anappropriate culture condition for producing various celllineages from HFSCs. Therefore, these stem cells areconsidered as a novel source for cell therapy of a broadspectrum of neurodegenerative disorders. This reviewpresents the current status of human, rat, and mouseHFSCs from both the cellular and molecular biologyand cell therapy perspectives. The first section of thisreview highlights the importance of HFSCs and in vitrodifferentiation, while the final section emphasizes thesignificance of cell differentiation in vivo .