The experience of having had intercourse with the devil has in the past been regarded as evidence that the individual is a witch. Those investigating cases of witchcraft were advised to seek the judgment of doctors, and the verdict of physicians became a test for the presence or absence of witchcraft. The woman described in this case study might well have suffered the death penalty in former times. She is unusual because of her belief that she had had intercourse with the Devil, and because the belief was shared by her religious minister. The patient also presents a diagnostic problem.