Results indicated that serial sex offenders were capable of a costs-benefits analysis of their actions. Their decisionmaking process underscored the importance of both personal and situational factors, including victim resistance. The findings suggest that rational choice theory can be relevant to the study of sex offenders and also suggests that a greater understanding of sex offender behaviors will come from a greater knowledge of victim behavior. Future research should incorporate both personal and situational factors in order to gain a greater understanding of the offending process and decisionmaking process of sex offenders. Participants were 69 serial sexual offenders recruited from a penitentiary of the Correctional Service of Canada. Semistructured interviews were conducted to identify the rationale driving their actions during the precrime phase, the crime phase, and the postcrime phase. Data were analyzed by breaking down the sex offender decisionmaking process into a series of sequential events. Descriptive statistics were then used to describe each category of events. Figures, references