The present paper reviews the empirical literature on the proportion of child sexual abusers who were themselves sexually victimized as children. While findings in individual studies ranged between 0% and 67%, on average about 28% of the offenders reported being sexually victimized as children. This rate is higher than the base rate for community samples of non-offending males (about 10%), but is similar to the rates found in other sexual or non-sexual offender populations. The relationship between childhood sexual victimization and sexually abusing children as an adult does not appear to be specific; rather, it is probable that many forms of childhood maltreatment can lead to many forms of behavioral and psychological problems in adulthood.