While theoretical models of sexual aggression against women have identified several variables related to rape proclivity, few have examined the process through which deviant sexual preferences develop. The current study assessed 118 adult male sexual aggressors against women who were processed through the Regional Reception Center, a maximum-security penal institution in Canada, between 1995 and 2000. Participants completed a self-administered computerized questionnaire which probed issues related to developmental factors, crime factors, and psychological characteristics. Questionnaires were based on semi-structured interviews conducted with participants. Of the total sample, 102 participants underwent phallometric assessment using French translations of audiotaped stimuli. Results of multiple regression analyses indicated that a sexually inappropriate family environment, use of pornography during childhood and adolescence, and deviant sexual fantasies during childhood and adolescence were associated with the development of deviant sexual preferences. These findings are consistent with theoretical explanations related to the proclivity to commit rape. The findings also support the model proposed by Knight and Sims-Knight involving three developmental pathways to sexual deviance. Given the moderate level of explained variance in the current study, future research should investigate additional variables in the etiology of sexual deviance among male rapists. Limitations of the current study include its small sample size; future studies should strive for larger samples. Tables