It's difficult to say which DBT skill is the most effective as different skills may be more helpful for different individuals depending on their unique circumstances and challenges. However, some of the most commonly used and effective DBT skills include: Mindfulness, Distress Tolerance, Emotion Regulation, and Interpersonal Effectiveness. Ultimately, the most effective DBT skill will vary from person to person based on their individual needs and goals in therapy. It's important to work closely with a trained DBT therapist to determine which skills will be most helpful for you.