This project expands our existing psychological services clinic (the Dialectical Behavior Therapy Clinic at Rutgers University; DBT-RU) to include an adolescent treatment arm. Adolescents aged 13-20 and at least one caregiver will be recruited to participate in a six-month treatment study. Adolescents will be eligible to participate if they meet at least 3 criteria for borderline personality disorder, with one of those criteria being either impulsive behavior or recurrent self-harm behavior. Participants will be assessed at baseline, three-months (mid-treatment), six-months (post-treatment, and three-month follow-up.

Inclusion Criteria:

• Age 13-17 years or 18-20 if still living at home with parent.
• Agreement of at least one responsible adult parent/caregiver to participate in treatment.
• Agreement to take part in assessments, videotaping/audiotaping and coding of their sessions by research personnel.
• Agreement to pay for mental health services at the DBT- RU on a sliding scale, and to participate in research assessments as volunteers.
• Residence within commuting distance of clinic (< 45 minutes).
• Agreement to discontinue other forms of talk therapy for duration of DBT program (does not refer to AA/NA programs or psychotropic medication management).
• Exhibits dysregulation within the past six months as evidenced by 1) intentional self-injury and/or suicide attempt and/or 2) substance use disorder.
• Meets two additional criteria for borderline personality disorder (BPD).

Exclusion Criteria:

• Clients who need mental health services not available at the DBT- RU, such as treatment for schizophrenia or life-threatening anorexia, or who are currently obtaining optimum professional treatment that should not be ended.
• Non-English speaking.
• IQ < 70.
• Unable to understand research consent forms.
• Court-ordered to participate in treatment.