Dialectical Behavior Therapy (DBT) is a form of psychotherapy developed by Marsha Linehan to help people with borderline personality disorder. However, DBT is also effective for other mental illnesses, such as depression, eating disorders, addictions, and post-traumatic stress disorder.

DBT is an evidence-based therapy based on the concept of dialectics. Dialectics is a philosophy that states that there are two opposing forces that are in conflict with each other but can work together to create something new. DBT is about balancing these forces, often referred to as "acceptance" and "change."

The DBT consists of four components:

1. Individual Therapy: Individual therapy is at the core of DBT. The therapist works with the patient to identify their goals and teach them the skills necessary to achieve those goals.
2. Group Therapy: Group therapy offers patients the opportunity to meet and learn from others who have similar problems. The group is led by a therapist who teaches clients how to use their skills in social situations.
3. Telephone coaching: The patient has the opportunity to contact their therapist outside of the therapy sessions if they find themselves in a difficult situation. The therapist can then help apply the skills learned in therapy to deal with the situation.
4. Skills Training: In the skills training sessions, patients learn specific skills to manage their emotions, build relationships, and change their thoughts and behaviors. The skills are taught in four modules: mindfulness, interpersonal effectiveness, emotion regulation and stress tolerance.

DBT aims to help patients live "life worth living" by teaching them skills to manage their emotions, improve their relationships, and change their thoughts and behaviors. DBT has proven effective and is used worldwide to help people with mental illness.