The phenomenon discovered by the famed New York Dermatologist, Norman Orentriech, in the 1950s that when hair was transplanted from the back of the head into the balding frontal region would continue to grow and not be lost, i.e., the transplanted hair would maintain the characteristic of the donor site and not be influenced by the recipient site. This is the principle of modern hair restoration but is not entirely true as the recipient site can have some influence.