These opposing hypotheses were analyzed using data collected from 83 victim self-report questionnaires and a review of 36 investigated police reports in England. Results showed homosexual offenders were more likely to have known their victims for some time and target those under 25 years of age. Heterosexual offenders tended to attack strangers of all ages and were more likely to operate in gangs. A comparison of the two samples revealed acquaintance sexual assault was less likely to be reported to the police, drawing attention to the fact that different explanations may be strongly influenced by the particular sample under study. Results also highlighted the need for additional research to explore different groups of male rapists. 13 references, 2 notes, 5 tables, and 5 figures