Protocol Development of Sage: A Novel Conjoint Intervention for Suicidal and Self-Injuring People With Borderline Personality Disorder and Their Significant Others

Borderline personality disorder (BPD) is associated with several destructive behaviors, including suicide and nonsuicidal self-injury. The devastating effects of BPD impact individuals with BPD, their relationships, and the mental health of significant others (SOs), which research suggests may be suboptimal. Few BPD interventions incorporate SOs into treat-ment, despite research suggesting that both emotion dysregulation and relationship dysfunction contribute to the mainte-nance of BPD. Incorporating SOs into treatment presents an opportunity to optimize BPD outcomes, while dismantling emotional and relational factors that maintain BPD and improving SO mental health. This paper describes the develop-ment of Sage, a 12-session conjoint psychotherapy intervention delivered to individuals with BPD who engage in suicidal and nonsuicidal self-injurious behavior, or have suicidal ideation, and their SOs. It is designed to simultaneously target BPD pathology, relationship functioning, and SO mental health. Sage is a time-limited cognitive-behavioral intervention that is primarily informed by cognitive-behavioral conjoint therapy for posttraumatic stress disorder (Monson & Fredman, 2012) and dialectical behavior therapy (Linehan, 1993, 2015). This paper describes the development of the intervention, including key skills taught, logistical issues that were encountered in its delivery, and relevant solutions. Future directions in the development and testing of Sage are described.