[The causality principle of psychotherapy and supportive methods in group psychotherapy--reflections on the principles of method combinations].

A causality principle of psychotherapy is offered, starting from a technologically orientated concept of psychotherapy as a process. Working from target, commencement, principles, and means, psychotherapeutic methods may be characterised. From these, rules governing the therapist's mode of conduct are arrived at. The causality principle provides a theoretic and practical basis for the integration of ancillary methods into various therapeutic concepts, and for therapeutic teamwork.