Dialectical behavior therapy (DBT) is an evidence-based treatment initially developed for individuals meeting criteria for borderline personality disorder (BPD) and has been adapted for various populations, including adolescents. As many problematic behaviors in adolescents, including suicidal ideation and non-suicidal self-injury, are often the result of deficits in emotion regulation systems, DBT provides a vital framework for treatment. This chapter explores the historical development of DBT, its theoretical foundations, and its core treatment components, including individual therapy, skills training groups, phone coaching, and consultation teams. Additionally, the chapter outlines the five DBT skills modules—mindfulness, distress tolerance, emotion regulation, interpersonal effectiveness, and walking the middle path—demonstrating their applicability to adolescents and their families. Finally, the chapter highlights empirical evidence supporting DBT’s efficacy in reducing self-harm, suicidal behaviors, and emotional dysregulation in adolescent populations. Special attention is given to the biosocial theory of emotion dysregulation, the role of family involvement in treatment, and the significance of accurate assessment for DBT fit. The goal of this chapter is to equip mental health professionals with the foundational knowledge necessary to identify adolescents who may benefit from DBT, understand its treatment philosophy, and incorporate DBT-informed strategies into clinical practice.