The relative efficacy of both group and individual cognitive behavior therapeutic approaches in treating anxiety and depression are evaluated and then compared to an interpersonal group therapy approach. The two major hypotheses are that group cognitive behavior therapy is at least as effective as individual cognitive behavior therapy, and that group or individual cognitive behavior therapy is significantly more effective than interpersonal group therapy. The 44 subjects, ranging in age from 21 to 41, were all seeking relief from symptoms of anxiety and/or depression. They were randomly assigned to one of three treatment modalities: (1) cognitive behavior therapy group, (2) interpersonal group therapy or (3) individual cognitive behavior therapy. The three treatments were compared as to their efficacy with this patient population. Results indicated that cognitive behavior therapy in a group format was as effective as individual cognitive behavior therapy in producing significant improvement in depression, anxiety, and assertiveness. All three experimental groups improved significantly from pre to post treatment on all dependent measures. An inverse relationship was found between depression and assertiveness and between anxiety and assertiveness on both pre- and post-treatment measures. (Author/BMW)