The basic principles of the phenomenon "erection" have been known since the pioneering work of Kolliker, Eckhard and Langley in the nineteenth century. Nonetheless, under the influence of Freud, erectile dysfunction was predominantly at tributed to psychogenic factors. A more liberal perception of sexuality since the 1960s, the development of new and refined diagnostic techniques, and the expansion of basic research activity resulted in a new concept of erectile dysfunction, identifying ar...