This systematic review recommends against policies facilitating the transfer of juveniles from juvenile to adult criminal justice systems for the purpose of reducing violence based on strong evidence that these laws and policies are associated with increased subsequent violent behavior among transferred youth. There is insufficient evidence to determine whether juveniles in the general population are deterred from violent crime by strengthened juvenile transfer policies. Transfer refers to placing juveniles under the jurisdiction of the adult criminal justice system, rather than the juvenile justice system, following arrest. Transfer is also referred to as waiver, denoting the waiver of authority by the juvenile court that allows for transfer of a juvenile defendant to an adult criminal court. Policies regarding the placement of juveniles in the juvenile or in the adult justice systems are largely determined by each state. Several legal mechanisms are used for the transfer of youth under the age of 18 years from the juvenile court system to the adult criminal system. Transfer can be at the discretion of the judge, or be mandated by law, for example for specified serious crimes. This review assessed policies that mandate or facilitate such transfers under some circumstances.