Stress may be a source of sexual problems, sex may be a source of stress, or stress may even be a facilitator of sexual response. Sexual dysfunction is often associated with anxiety, and physical illness can impair sexual response. Traumatic experiences of a sexual nature can have important adverse effects, although this is not always the case. Rape and incest provide pertinent examples. Sexual activity has been implicated in both physical and psychiatric morbidity but there are a number of methodological difficulties in interpreting these associations, as illustrated by the 'coital coronary'. Stress does not invariably exert negative effects on sexual response and anxiety arousal can sometimes facilitate sexual arousal in both men and women,