This definitive work on juvenile court law (JGG: Jugendgerichtsgesetz) is fully brought up to date in the 12th edition. The commentary's guiding principles remain focused on the basic ideas of the JGG, according to which further breaches of the law by juveniles and young adults should be prevented via juvenile penalties that are constitutional and educationally structured. The integration of young people into society should also be facilitated. This commentary offers essential guidance to all practitioners active in the field of juvenile criminal justice.