Imaging methods are essential in the diagnosis of erectile dysfunction. With sonography the penile cavernous tissue and the deep arteries can be shown. This visualization is optimized by high-resolution ultrasonography with pulsed Doppler spectrum analysis or angiodynography. Pharmacocavernosonography combined with pharmacocavernosometry is the method of choice to verify pathologic venous leakage from the penis. Phalloarteriography is absolutely necessary before surgery for revascularization of the penis. In investigations of fertility sonography of the scrotum only plays a subordinate role, as an occlusion of the epididymis cannot be diagnosed in this way. In contrast, good visualization of any small intraparenchymous tumor of the testicle is possible. Transrectal sonography allows the best assessment of the vesicular glands. A persisting varicocele is visualized by retrograde phlebography of the internal spermatic vein. Antegrade phlebography of the spermatic vein with Valsalva maneuver is used by some workers in preference to the above-mentioned method, but has not yet been fully evaluated. Scrotal thermography can visualize a varicocele in a satisfactory manner. Obstacles to ejaculation can sometimes be visualized with retrograde urethrography and/or voiding urethrography. Focused x-rays of the sella turcica are necessary if there is any suspicion of a prolactinoma. Mammography will help to differentiate between gynecomasty and alimentary pseudo-gynecomasty. CT and NMR are used to diagnose tumors of the adrenal and pituitary glands; these methods are rarely used to diagnose abdominal cryptorchidism. Radiologic representation of the ductus deferens with contrast medium (vasography) now has to be rejected as harmful and obsolete.