The downloading and possession of Child Sexual Exploitation Materials (CSEM; also referred to as child pornography and indecent images of children) is the most commonly convicted type of internet sexual offences. This review summarizes the current state of knowledge on CSEM offenders. We first provide a summary of the key motivations of CSEM offenders, characteristics of CSEM offenders compared to contact sexual offenders against children, and important facilitative factors. We then review the factors related to recidivism among CSEM offenders. Finally, we describe current developments in the risk assessment, police case prioritization, and treatment approaches for CSEM offenders. Generally, CSEM offenders are found to hold a sexual interest in children, to be low on antisocial tendencies, and to pose a low risk to reoffend (including contact sexual offending). Key facilitative factors for CSEM offending include access to children, offence-supportive cognitions, and sexual arousal. Factors indicative of antisocial tendencies (e.g., criminal history) are associated with an increased risk of reoffending. Lastly, addressing atypical sexual interest, socio-affective dysfunctions, and strategies for maintaining an offence-free lifestyle are key treatment targets for CSEM offenders. Lower treatment dosage, however, should be considered given the lower risk level of CSEM-exclusive offenders. We hope that this review will inspire others to explore the current research gaps in future studies
