Current American policies and responses to juvenile sex offending have been criticized for being based on myths, misconceptions, and unsubstantiated claims. In spite of the criticism, no organizing framework has been proposed to guide policy development with respect to the prevention of juvenile sex offending. This article proposes a developmental life course (DLC) criminology perspective to investigate the origins, development, and termination of sex offending among youth. It also provides a review of the current state of knowledge regarding various parameters characterizing the development of sex offending (e.g., prevalence, age of onset, frequency, persistence, continuity in adulthood, and versatility). The review highlights some heterogeneity across these developmental parameters suggesting the presence of different sex offending patterns among youth. In fact, it is proposed that, based on the current knowledge, such heterogeneity can be accounted for by a dual taxonomy of adolescents involved in sexual offenses: (a) the adolescent-limited and (b) the high-rate/slow-desister. The DLC criminology approach and the dual taxonomy are proposed as organizing frameworks to conduct prospective longitudinal research to better understand the origins and development of sex offending and to guide policy development and responses to at-risk youth and those who have committed sexual offenses.