Article 55 of the UN Charter gives it a wide mandate in several fields of societal development, including crime and criminal justice. In addition to its self-evident role as a global body seeking to prevent such international crimes as terrorism and narcotics trafficking, the UN seeks to assist member States in improving their domestic criminal justice systems. To promote training, research, and regional cooperation, the UN has established a network of inter-regional and regional institutes. Important network components include the exchange of information on crime and criminal justice, the establishment of data bases, technical assistance, research, training, and the formulation and implementation of international standards. Juvenile delinquency is an important aspect of the UN's criminal justice policy framework. The UN has historically emphasized social defense in juvenile criminal policy and has sought specifically to promote medical and educational measures that rehabilitate children with antisocial tendencies, to organize vocational training for children who leave school, and to treat juvenile offenders according to medical and educational methods in which punishment is administered by special measures. Since 1955, the UN has sponsored several congresses dealing specifically with juvenile justice.