In many modern states, with regard to the recommendations of international documents, the aim is to act in a manner so that the negative effects on personality in young offenders caused by conducting of trial proceedings shall be avoided. The efficiency principle is applied in our legislative system and the Juvenile Courts Act (Official Gazette no. 56/2015) makes it possible to apply it in at all stages of a process considering minors in conflict with the law. In this work, special emphasis shall be put on the application of the efficiency principle in the preparation procedure where a decision not to initiate infringement proceedings is made by the prosecutor and that decision may be made conditional upon, inter alia, the minor's willingness to include in mediation procedure through an out-of-court settlement. The applied type of out-of-court settlement is a concept of restorative justice. The parties participating in the mediation process are the offender and the victim, as well as the professional intermediary with the aim to resolve the consequences of the offence. The aim of this model is to protect the victims, to provide a compensation caused by the offence, offender's accountability for behaviour, the opportunity for the victim to share how it influenced it and the voluntariness of all parties included. In order to understand the model of the out-of-court settlement better, the work shall theoretically and up to some details include its significance, purpose and course, as well as some researches that shall be mentioned in order to evaluate the efficacy of this model.