The system of dealing with children in trouble with the law has existed for more than a century, starting with the creation of separate institutions for juvenile delinquents and "at-risk" children, which was soon followed by a series of regulations. Although different models have been in place from the very beginning, the predominant approach has been one focused on ensuring the well-being of the child, i.e. ensuring the best interests of the child. This approach is based on the concept of intervention in the best interests of children, which focuses on their needs, not their actions, and which is based on the involvement of social workers to assist the court in matters within their professional competence. Often around such juvenile justice systems there are socio-therapeutic and educational institutions for the rehabilitation and reintegration of juvenile offenders or those at risk of becoming one. Other juvenile justice systems that may be considered distinctive are based on a justice system that more closely resembles the criminal justice system for adults, or administrative commissions or other informal justice processes. In some countries, there are no (or very few) special provisions for juvenile offenders. As a result, there are huge differences in the forms and types of courts, services and institutions that make up the juvenile justice system. With regard to children in conflict with the law, the main aspect is that in criminal proceedings the latter, due to their age and immaturity, are assigned a separate regime, different from that applied to adult offenders. The prerequisite for this is the special vulnerability and limited capabilities of children whose development process has not yet been completed. Not only should any actions be evaluated in accordance with the standards of ensuring the best interests of the child, but the system itself should be responsive to the child's developmental needs in care, in order to ensure the reintegration of children into society as law-abiding citizens. Therefore, the juvenile justice system should focus its attention not only on the nature of the offense committed, but also on the root causes of its commission, as well as on the specific circumstances of each child.