The most authoritative thinking on the most pressing questions, issues, and controversies in psychotherapy research and practice. Historical and Methodological and Ethical and Conceptual Foundations, Introduction and Historical Overview, Methodology and Design and Evaluation in Psychotherapy Research, Theoretical Challenges to Therapy Practice and Research: The Constraint of Naturalism, Methodological Issues in Studying Psychotherapy Processes and Outcomes, Evaluating the Ingredients of Therapeutic Efficacy, The Efficacy and Effectiveness of Psychotherapy, The Influence of Client Variables on Psychotherapy, Therapist Variables, Fifty Years of Psychotherapy Process-Outcome Research: Continuity and Change, Major Approaches, Behavior Therapy with Adults, Cognitive and Cognitive Behavioral Therapies, Research on Experiential Psychotherapies, Research on Applications in Special Groups and Settings, Psychotherapy for Children and Adolescents, Health Psychology, Combining Psychotherapy and Psychopharmacology for Treatment of Mental Disorders, Research on Psychotherapy with Culturally Diverse Populations, Index.