CBT is a form of psychotherapy that emphasizes the important role of thinking in how we feel and what we do. It is based on the idea that our thoughts cause our feelings and behaviors, not external things, like people, situations, and events. It focuses on the "here and now", and on alleviating symptoms. The aim is to help people solve problems concerning dysfunctional emotions, behaviors and cognitions through a goal-oriented, systematic procedure in the present. There is empirical evidence that CBT is effective for the treatment of a variety of problems, including mood, anxiety, personality, eating, substance abuse, and psychotic disorders. CBT is structured and directive, and tends to be brief.