Behavioural problems are a recurring issue in the child welfare system population. Normative residential centres do not have the characteristics to address the specific needs of these adolescents, so they are usually treated at therapeutic residential centres. In Catalonia (Spain), these cases are treated in intensive educational residential centres (CREIs), a variant of therapeutic residential care (TRC) facilities. This exploratory study seeks to understand the treatment progress of adolescents with severe behavioural problems who were placed in the CREIs, a variant of TRC facilities. Data from 206 cases, the totality of population under treatment in the CREIs, were collected using a questionnaire administered to the treating team. A cross-sectional design was used, applying quantitative methods to analyse the incidence and interrelation of a series of variables related to the progress of adolescents in the CREIs. Significant differences among profiles by sex, place of origin, criminal offences, substance abuse and mental health disorders were found. Furthermore, adolescents who performed a positive treatment progress according to the professional staff arrived at the CREI at an earlier age and had longer stays than the group with an unremarkable progress. Logistic regression indicated that duration of stay in the centre and runaways predict the adolescents' treatment progress. This treatment is working well with the milder cases; however, it does not tend to be successful for adolescents with greater difficulties. It is recommended that interventions focus on factors that engage the adolescents in their own rehabilitation process, include substance abuse programmes and consider the gender perspective.