In 2001, Bruce Wampold of the University of Wisconsin published the book The Great Psychotherapy Debate . [ 31 ] In it Wampold, a former statistician who went on to train as a counseling psychologist, reported that psychotherapy is indeed effective, the type of treatment is not a factor, the theoretical bases of the techniques used, and the strictness of adherence to those techniques are both not factors, the therapist's strength of belief in the efficacy of the technique is a factor, the personality of the therapist is a significant factor, the alliance between the patient(s) and the therapist (meaning affectionate and trusting feelings toward the therapist, motivation and collaboration of the client, and empathic response of the therapist) is a key factor. Wampold therefore concludes that "we do not know why psychotherapy works". http://en.wikipedia.org/wiki/Psychotherapy#Criticisms_and_questions_regarding_effectiveness http://www.education.wisc.edu/cp/faculty/boo...