The two chapters of Part I offer a foundation for a developmental perspective on juvenile justice. The seven chapters of Part II address the presumption that youths are capable of participating meaningfully in their trials in adult criminal courts based on the fact that they are charged with serious offenses. Theory and research from psychology, psychiatry, and law are applied to questions of youths' capacities to understand and decide important matters as defendants in their trials. Chapters also review the challenges that youths' immaturity present for their attorneys, as well as clinical and forensic issues in assessing youths' competence to stand trial. The six chapters of Part III focus on issues associated with the culpability and diminished capacity of juveniles when determining appropriate dispositions. These matters are relevant when policymakers are determining whether juveniles should be sentenced the same as adults for the same offenses. The chapters address this issue by drawing on pertinent legal precedent and theory, as well as empirical knowledge of the psychological and social capacities of youth relative to those of adults. Underlying all the chapters is the assumption that an effective legal response to youthful offenders must take into account the developmental realities of adolescence. For individual chapters, see NCJ-184853-68. Chapter references, notes, tables, and figures