Erectile dysfunction is a complex syndrome associated and determined by several separate vascular and nonvascular factors. In recent years, the evolution of noninvasive vascular technology used to investigate macro- and microcirculation in vascular disorders has produced a large amount of information and increased our knowledge of vascular pathophysiology. Andrea Ledda and his clinical research group, well known to their international colleagues, describe new developments in andrology and stress the importance of vascular disorders in erectile dysfunction. This volume will be very useful to andrologists, vascular surgeons, and angiologists, and to all specialists interested in the diagnostic evaluation of erectile disorders and varicocele.