The hypothesis that premature ejaculators (PEs) are less able than non-premature ejaculators (NPEs) to evaluate accurately their level of physiologically determined sexual arousal was tested. Twenty-six men (13 PEs and 13 NPEs) viewed a variety of videotaped vignettes, some of which were excerpts from sexually explicit films. Concurrent subjective (self-report) and objective (plethysmograph) ratings of sexual arousal were taken. Data revealed that both the PEs and NPEs were equally accurate in assessing their level of physiological sexual arousal. These results and those from a sexual history questionnaire were used to evaluate several hypotheses regarding the nature and etiology of premature ejaculation.