Although the investigative techniques discussed may be used in other cases of sexual victimization of children, they are intended to be applied primarily to the investigation of sexual victimization of children by adult acquaintances, who often gain access to potential child victims by becoming involved in youth-serving organizations. In order to successfully investigate and prosecute cases that involve the sexual exploitation of children by acquaintance child molesters, four significant behavioral concepts of this relatively common type of child sexual victimization must be understood. These key dimensions include sexual activity, "nice-guy" offenders, compliant child victims, and grooming/seduction. The fist concept, sexual activity, involves understanding the nature and scope of behavior that can constitute sexual activity. The concept of the "nice-guy" offender involves understanding the offender who seems to love and is often loved by children. Acquaintance offenders typically sexually exploit children through the seduction and/or the collection, creation, or distribution of child pornography. The third concept, compliant child victims, involves understanding children who are or were compliant in their victimization. The fourth concept for developing an enhanced insight into acquaintance molesters involves understanding the grooming/seduction process used by such offenders in attempting to achieve consensual sexual contact with a victim. In elaborating on these key concepts, the author weaves them into techniques for investigating acquaintance sexual exploitation cases. Related issues discussed are the collection and use of child pornography by such offenders; technology-facilitated cases; and investigative challenges in dealing with child victims, societal attitudes, and investigators criticized for investigating "nice-guy" offenders. Appended references, relevant appellate case decisions, and the investigator's "basic library"