Cross-cultural comparisons may also be restricted by linguistic problems, cultural concepts, different parameters of illegal behavior, different definitions of delinquency, and different ages of majority. However, in all circumstances, researchers and policymakers must differentiate between juvenile and adult offenders for several reasons: juvenile behavior is not readily explainable by theories of criminal behavior, juveniles may have contact with the criminal justice system because of a wide range of behaviors and victimization situations, most juveniles are not committed to a life of criminal behavior, and juveniles are more likely to be amenable to treatment than adults. The authors of articles included in this special issue have pointed out the lack of reliable and valid information regarding juvenile offenders and emphasized the need to collect more data on delinquent behaviors and on the institutional responses to those behaviors.