We examined whether an erotic response to cross‐dressing fantasies could be detected in heterosexual male cross‐dressers (HCDs) who verbally denied any erotic arousal in association with cross‐dressing for at least the past year. Subjects were 37 HCD patients and 10 paid heterosexual controls. HCDs were divided into groups according to their response to a questionnaire item asking the proportion of occasions that cross‐dressing was erotically arousing during the past year and offering response options from always to never. Penile blood volume was monitored while subjects listened to descriptions of cross‐dressing and sexually neutral activities. All HCD groups responded significantly more to cross‐dressing than to neutral narratives (p < .01); controls did not. Results suggest that only those causal hypotheses of heterosexual cross‐dressing need be considered that can account, also, for the presence of fetishism.