With this invited commentary we want to draw the attention of young medical doctors, the main readers of this journal, towards the existence and importance of a group of nanovesicles released by human cells: the exosomes. These vesicles are incontinently se-creted as a mean of cell-to-cell communication. They are involved in a number of physiol-ogic processes as well as in the pathogenesis of, virtually, all human diseases. They can be isolated from all biological fluids, like blood, urine, sweat, sperm, crevicular fluid, bile, etc., and their composition in terms of proteins, RNA and lipids is different in pathology that in physiologic conditions. It is therefore possible to predict that they will become an important diagnostic and therapeutic tool in medicine.