Psychotherapy utilizes clinical techniques based on psychological principles in the context of a collaborative therapeutic relationship to enable people to develop adaptive responses to behaviors, beliefs, cognitions, or emotions they find problematic. Various clinical methods and interpersonal stances have been reviewed with regard to therapeutic process factors and their impact on the course and outcome of treatment. As interest has turned from testing the comparative efficacy of treatment types to examining the common factors that account for the overall effectiveness of psychotherapy, aspects of the therapeutic process have been considered as emerging context for successful therapy, as change mechanisms producing outcomes, or as ultimate outcomes of therapy.