This study examined MASTR/EMDR, a trauma-focused treatment for traumatized youth taken in charge by youth protective services. Participants were 40 adolescents (ages 13-17) exhibiting conduct problems, internalizing and externalizing behaviors and who have been exposed to maltreatment. Participants were randomly assigned to MASTR/EMDR treatment or to a routine care condition. Self-report questionnaires and semi-structured interviews were administered to participants and one of their parents/caregivers at three points in time: pre-treatment, post-treatment (12 weeks) and follow-up (12 weeks). Repeated measures ANCOVAs showed that participants in the experimental group had significant improvements in their trauma symptoms and behavioral problems compared with the control group at the post-treatment evaluation. These effects were maintained at a 3-month follow-up. Results support the effectiveness of MASTR/EMDR.