BEHAVIOn ~-~g~Y 21, 111-116, 1990 The Relationship Betwocn Therapist Characteristics and Outcome of In Vivo Exposure Treatment for Agoraphobia K. ELAINE WII.tTAM.~ DIANNE L. CHArtLESS The American University The relationship between six therapist characteristics and outcome of in vivo ex- posure treatment for 33 agoraphobic clients was examined in a prospective study. Clients who rated their therapists as more self-confident and those who perceived their ther- apists to be more caring and involved were significantly more likely to improve on a behavioral avoidance test. Contrary to prior retrospective research, therapists' being perceived as explicit or challenging was not a significant predictor of outcome. Although it has long been accepted that therapist characteristics influence client improvement in client-centered therapy (e.g., Barrett-Lennard, 1962; Rogers, 1957; Truax, 1963), few investigators have examined the possible im- pact of therapist qualities on the outcome of in vivo exposure treatment. Since the exposure therapist must persuade a client to enter and remain in highly feared situations, the quality of the relationship might well be pertinent for such behavior therapy as well. Indeed, agoraphobic clients undergoing imag- inal or in vivo exposure have been found to retrospectively rate interactions with a sympathetic, encouraging therapist as being more important to their improvement than specific exposure-related variables (Mathews et al., 1976). Rabavilas, Boulougouris, and Perissaki (1979) retrospectively examined the relationship between clients' perceptions of the therapist (e.g., empathy, ex- plicitness, encouragement) and in vivo exposure outcome for a mixed sample of 36 phobic and obsessive-compulsive clients. They reported a number of significant relationships between clients' improvement and therapist variables. Similar findings were retrospectively obtained by Emmelkamp and van der Hout (1983) with a small sample of agoraphobics. The results of a prospective study by Gustavson, Jansson, Jerremalm, and Ost (1985) with 12 agoraphobic clients receiving in vivo exposure would appear to contradict those of the prior The authors wish to thank the staff of the Agoraphobia and Anxiety Treatment Center, Bala- Cynwyd, PA, for the assistance in data collection in the measurement reliability phase of this study. Requests for reprints should be sent to Dianne Chambless, Ph.D., Dept. of Psychology, The American University, Washington, DC 20016-8062. 111 0005-7894/90/0111-011651.00/0 Copyright 1990 by Association for Advancementof Behavior Therapy All fights of reproduction in any form reserved.