Participants (n = 134) treated in a randomized controlled trial with mentalization-based treatment (MBT) compared with structured clinical management were followed up for 8 years after starting treatment in terms of the initial primary outcome of the trial—namely, suicide attempts, self-harm, and hospitalization—as well as service use and functional outcomes. Patients in the study group were interviewed by research assistants who remained masked to the original group allocation. Interviews were scheduled annually. Of the original participants, 98 (73%) agreed to participate. Overall, the beneficial outcomes at the end of treatment were maintained in both groups. Over the follow-up period, the number of patients who continued to meet the primary recovery criteria was significantly higher in the MBT group (74% vs. 51%). Use of most other services was comparable. Participants treated with MBT showed better functional outcomes in terms of being more likely to be engaged in purposeful activity and reporting less use of professional support services and social care interventions. (PsycInfo Database Record (c) 2021 APA, all rights reserved)