Accurate estimates of true and false child sexual abuse evades researchers and the determination of whether sexual abuse has occurred is a complex problem. In recent years, the research community has been polarized over whether child victims of sexual abuse or nonabuse are grossly misidentified, to what degree children are suggestible, and whether false positive or false negative errors create the greatest harm. This chapter describes the scientific‐practitioner model for evaluating allegations of child sexual abuse, a model previously proposed by the author. According to this model, conclusions regarding child sexual abuse are based upon empirically established relationships between data and the behavior in question, rather than on subjective opinions. To address critical issues in these assessments, this chapter reviews two sources for information: published research and the law. Child sexual abuse is defined, focusing on risk factors for abuse and the meaning of symptoms. Studies citing the incidence and prevalence of child sexual abuse are reviewed. Topics include early memories, the impact of stress on memory, and the development of autobiographical memory. Since recall is subjected to the effects of suggestibility, research on this topic is considered. The structure of the assessment interview and a review of the research on the three most frequently used evaluation tools (anatomical dolls, projective instruments, and drawings) is described.