In 35 men with organic impotence we have tested a noninvasive device which uses a vacuum to produce an erection-like state and rubber bands to maintain this state. The subjects were first evaluated to determine the cause of their impotence and to establish that it had an organic basis. Using this device 32 of the 35 subjects achieved penile rigidity sufficient for vaginal penetration. Subjects were studied with the rubber bands constricting the base of the penis for thirty minutes. During that period, blood flow continued, but at a less than normal rate. Of 30 men followed up from eight to twenty-two months, 24 use the device regularly and report that they are satisfied. Four subjects have not yet tried to use it, and 1 no longer needs it. One man was dissatisfied because the rigidity begins to decrease after five to ten minutes of sexual activity, even though it did not change over a thirty-minute period when originally tested in the laboratory. Ecchymoses of the penis, probably due to excess vacuum, developed in 3 subjects. In 8 other men petechiae of the skin of the penis developed on one or more occasions. These ecchymoses and petechiae were painless and disappeared without treatment. No other complications occurred. The vacuum device appears to be a safe and inexpensive way for an impotent man to make the penis rigid enough to engage in sexual intercourse.