A recently developed cognitive-behavioral treatment for generalized anxiety disorder (GAD) targets intolerance of uncertainty by the reevaluation of positive beliefs about worry, problem-solving training, and cognitive exposure. As previous studies have established the treatment's efficacy when delivered individually, the present study tests the treatment in a group format as a way to enhance its cost-benefit ratio. A total of 52 GAD patients received 14 sessions of cognitive-behavioral therapy in small groups of 4 to 6 participants. A wait-list control design was used, and standardized clinician ratings and self-report questionnaires assessed GAD symptoms, intolerance of uncertainty, anxiety, depression, and social adjustment. Results show that the treatment group, relative to the wait-list group, had greater posttest improvement on all dependent variables and that treated participants made further gains over the 2-year follow-up phase of the study.