The impact of psychotherapy supervision on client outcome: A critical examination of 2 decades of research

The supervision of counselors-in-training has become an important area of psychotherapy research. Through supervision, one expects that trainees will gain the knowledge and clinical skills needed to work effectively with clients. Much research has been dedicated to understanding trainee skill development through supervision, but relatively few studies in the literature have addressed whether clinical supervision leads to improved client outcome. The current article presents a review of 2 decades of research into the question of whether clinical supervision improves client outcome. Ten studies conducted between 1981 and 1997 are reviewed in detail. Caveats and criticisms, as well as suggested directions for future research, are discussed.