An analysis of research on juveniles notes that different authors reach different conclusions due to their differing definitions of youth, the group offending character of much juvenile crime, and changes in the population of juveniles. However, data show that young adults and older juveniles commit a high proportion of violent crimes. Nevertheless, two-thirds of a birth cohort of males are never seen in the criminal juvenile justice system, and a high proportion of the rest are only one-time offenders. Thus, caution is needed in predicting criminal behavior based on past offending. An analysis of careers of serious violent offenders concludes that arrest data may overstate the magnitude of sex, race, and age differentials in this population. In addition, serious violent offenders do not appear to be a unique class of offenders. Finally, the low probability of arrest for a serious violent offense means that assumptions are not justified that any offense is a first offense. An analysis of prevention and control programs for violent youths notes that many approaches have been tried, but little definitive knowledge has resulted from these efforts. However, it is clear that the most effective correctional strategies must limit the use of training schools and expand the range of community-based sanctions. Chapter reference lists.