The current study was designed to explore profiles of reactive and proactive aggression in two distinct juvenile offender populations, in a group of juvenile offenders who have been adjudicated for illegal sexual behavior (n = 138) and in a group of juvenile offenders adjudicated for general delinquent behavior (n = 243). This is the first study of its kind to investigate profiles of aggression in a population of juveniles adjudicated for illegal sexual behavior. Preliminary profile analyses indicated that the two juvenile offender populations had similar profiles of aggression overall. Two step cluster analysis results were generally consistent with previous research (Crapanzano, Frick, & Terranova, 2010; Marsee et al., 2014) with 3 groups emerging for both overt and relational aggression: a combined group high on both reactive and proactive aggression, a group high in reactive aggression alone, and a low overall group. Post hoc comparisons of the clusters revealed that the high combined group consistently demonstrated higher reports of emotional and behavioral dysfunction supporting the hypothesis that the presence of proactive aggression serves more as an indicator of severity rather than as representing a qualitatively distinct group in and of itself. Policy implications regarding sex offender registration and notification laws extended to juveniles are discussed.