Although borderline personality disorder (BPD) tend to the clinical remission in long-term follow-up studies, a significant subgroup of patients continues to present long lasting symptoms such as low mood, emptiness and persistent impairment in psychosocial adjustment. The prevalence of this subsample of individuals is considerably increasing last years. New interventions addressed to these individuals are need, the aim of this study is to evaluate the efficacy of a novel intervention combining dialectical behavioral therapy skills training with self-compassion and contextual-based skills for patients with long-lasting BPD.

Sixty individuals with BPD and long lasting symptoms that have been received previously dialectical-behavioral therapy skills training (DBT-ST) will be included in a randomized clinical trial. They will be randomly assigned to receive an add-on skills training intervention involving the combination of DBT-ST, self-compassion, and contextual-based skills for long lasting symptoms versus treatment as usual during 12-weeks. Patients will be evaluated pre and post intervention and 3-month follow-up. The outcome measures are well-being indicators and clinical variables.

Inclusion Criteria:

• Adults between 18 and 65 years of age
• Primary diagnosis of BPD according to Diagnostic Statistical Manual IV criteria and by the structured interviews: Diagnosis Structured clinical interview for axis II personality disorders (SCID II; First et al. 1997) and Diagnostic Interview for Borderlines Revised (DIB-R)
• Previous participation in DBT-ST intervention
• Signed informed consent.

Exclusion Criteria:

• Presence of life-threatening behaviors in the last 12 months
• PTSD or related symptoms
• Diagnosis of drug-induced psychosis, organic brain syndrome, bipolar or psychotic disorder
• Intellectual disability
• Participation in any other psychotherapy treatment during the study.