Internet offenders were significantly younger than the child molesters and were predominantly White; whereas, child molesters had more mixed ethnicity. Both types of sex offenders had experienced substantial levels of childhood difficulties, although the child molesters reported significantly more childhood physical abuse than Internet offenders. A significantly higher number of Internet offenders had contact with mental health services as an adult compared to child molesters, and Internet offenders had significantly fewer live-in relationships than child molesters. Internet offenders had significantly fewer previous sexual convictions; however, child molesters had no previous Internet pornography convictions. There were no major differences between Internet and contact offenders in personality or mental health functioning. There were relatively high levels of self-reported psychopathology, with 40 percent of the sample reporting the distinct presence of personality disorder. Both Internet offenders and child molesters presented with a more schizoid, avoidant, and dependent profile suggestive of individuals who retreat from interpersonal and social situations, sometimes fearing rejection and cutting themselves off emotionally from others. Over a period of 18 months at risk, Internet sex offenders were significantly less likely than child molesters to reoffend for all types of offenses. Data on all study participants were obtained from probation files and discussions with probation officers. Reoffending data were collected in a variety of ways. Probation and forensic mental health files contained data on inappropriate behavior that did not constitute criminal offenses. Data on reoffending encompassed all types of offenses. 7 tables and 28 references