Extracellular messenger vesicles known as exosomes are being investigated widely as a new therapy for hair loss. A wide body of preclinical research has demonstrated the potential of exosomes for hair regeneration. Exosomes can affect hair growth by targeting transport of molecular signals to hair follicle components and interacting with hair growth cycle regulation molecules. Preliminary human clinical data seem favorable. The molecular effects of exosomes on hair regeneration are not completely understood and may vary widely based on exosome source. Problems with unregulated human use have emphasized the need for greater standardization and control of exosome use.