title: Introduction to the special series on advances in psychotherapy process research.
authors.affiliation: University of Arizona.
authors.forename: L E
authors.initials: LE
authors.lastname: Beutler
mesh_terms: D005500:Follow-Up Studies; D006801:Humans; D009629:Person-Centered Psychotherapy / Q000379:methods; D010553:Personality Development; D011613:Psychotherapy / Q000379:methods*