Young offenders are defined as "that proportion of the New Zealand Department of Corrections offender population aged 17-20 years." Research indicates that only small proportions of youth, less than 10 percent, are at risk of becoming persistent offenders. The key characteristics of high-risk youth appear to be a history of antisocial behavior beginning at an early age; antisocial attitudes, values, and beliefs; antisocial associates; problems with interpersonal relationships; impulsive, aggressive temperament; problems at school, work, or leisure; and early and current family problematic conditions. The literature review examined a number of risk/needs classification systems and concluded that no adequate instruments have yet been developed for assessing young offenders in the New Zealand context. After reviewing a variety of specific treatment programs beginning with programs for violent young offenders, the study concluded that community-based programs have an advantage over institutional programs and are particularly successful when significant others in the youths' social sphere -- such as family, peers, and fellow gang members -- are also treated. The review noted a dearth of literature on substance abuse treatments for young offenders. Cognitive-behavioral and relapse prevention substance abuse treatments show promise, but more work is required in developing and evaluating these interventions with young offenders. There is a similar lack of recent research on the effectiveness of wilderness programs for young offenders. The review concludes that the outcome results of education/employment programs are equivocal, although well-implemented and well-run programs may have a significant impact on offending behavior. The review concluded that no single form of treatment will effectively reduce recidivism among young offenders. Effective programs tend to be empirically sound and clinically relevant to theories of criminality; are well-structured; have a cognitive-behavioral format; are multimodal; and address criminogenic needs. The review describes a number of institution-based, community-based, and aftercare services for young offenders. 187 references and appended tables