The goal was to collect information on a large sample of JSOs throughout the United States using a standardized instrument in order to get a clear descriptive picture of this population. The five goals of this study were to gain an understanding of the deviant sexual behaviors of JSOs; compare with a sample of adult offenders; learn more about the characteristics of offenses; explore the roles played by delinquent behavior and substance abuse; and assess truthfulness of responding and willingness to report inappropriate behaviors. Subjects completed the Abel Questionnaire for Boys, comprised of questions regarding demographics, “normal” sexual experiences, delinquent behaviors, substance use, sexual victimization, arousal to sexual vignettes, and social desirability. Results show that child molestation was the most commonly reported sexually deviant behavior; over 60 percent of the JSOs assessed had engaged in child molestation. Other commonly reported behaviors were pornography and fetishism, voyeurism, obscene phone calls, unwanted touching/rubbing, phone sex, and exhibitionism. The mean ages of onset for all behaviors were between 9 and 12. When compared with a sample of adults, juveniles reported higher frequencies for fetishism, obscene phone calls, child molestation, and phone sex. The largest percentage of JSOs was accused of molesting boys or girls at least 3 years younger than themselves. With the exception of belonging to gangs and quitting school, JSOs reported engaging in higher levels of antisocial behaviors than their friends. Substance abuse did not appear to play a major role. While nearly all respondents indicated that they had been fairly to completely honest, those with higher social desirability scores claimed to have been more honest in responding than did those with lower social desirability scores.