This introductory chapter presents the basic principles of the juvenile court. Foremost among these is the radical idea that the law should treat children differently from adults. The political philosopher John Locke argued that children's lack of reasoning capacity, which disqualified them from participating in government, also made them less culpable for their criminal acts. Another principle states that children's cases should be diverted from the destructive dynamics of the criminal justice system. This diversionary rationale made increasing sense in a society in which the modern ideal of a sheltered childhood became nearly universal by the middle decades of the twentieth century.