Ethical consent was obtained to extract information from the case files of a national specialist service. A description of characteristics was built up from variable frequencies and quantitative and qualitative analysis produced findings that indicated a family history of cross-generational harm to children and a parental experience of unresolved harm in childhood generated inconsistent and insensitive parenting that was linked to high levels of maltreatment and insecurity of attachment in the research group. Sexualized reactions by the research subjects to a very high level of sexual victimization were not responded to in a timely or appropriate way by parents, other caregivers or professionals so that sexually harmful behavior continued without intervention for a significant period. The study proposes a three-stage model that identifies predisposing vulnerabilities, sexual victimization as a trigger event and the subsequent development of sexually harmful behavior as a protecting adaptation that assumes an aroused and organized aspect through repetition. (Published Abstract)