This study was supported by a grant from CEJFE and Àrea de Medi Obert i de la Unitat de Programes d'Innovació de la Direcció General d'Execusió Penal a la Comunitat i de Justícia Juvenil, Department of Justice, Autonomous Government of Catalonia.The aim of the study is to evaluate the results of "Limits", a parenting training program which was implemented in a juvenile justice service by professionals from the Department of Justice. A controlled before and after design was undertaken to measure the effects of the program on the use of parental practices and parents' perception of self-efficacy. Fifty-nine families with adolescents involved in the juvenile justice system participated either in an intervention group (n = 42 families) or in a waiting list group (n = 17 families). In order to triangulate the information, professionals and the target adolescents were also asked about the improvement of the parents in their parenting practices. A generalized linear model was used to compare the intervention and comparison groups. The findings demonstrate that the program had a positive impact on the intervention group with regards to the transfer of practices to their real life, especially those related to communication and family relationships. However, no significant changes were observed in parents' perception of self-efficacy. The results are geared towards the improvement of future research evaluations using longitudinal designs
