A major option for many mental disorders is psychotherapy. There are several main types. Cognitive behavioral therapy (CBT) is widely used and is based on modifying the patterns of thought and behavior associated with a particular disorder. Other psychotherapy include dialectic behavioral therapy (DBT) and interpersonal psychotherapy (IPT). Psychoanalysis, addressing underlying psychic conflicts and defenses, has been a dominant school of psychotherapy and is still in use. Systemic therapy or family therapy is sometimes used, addressing a network of significant others as well as an individual.