This pilot investigation will examine the effectiveness of augmenting cognitive behavioral therapy (CBT) with antidepressant pharmacotherapy (escitalopram[Lexapro]) in adults with generalized anxiety disorder (GAD) who do not fully respond to a temporally primary trial of CBT. A secondary aim of this study is to assess the maintenance of treatment gains made by patients in response to CBT, and to CBT with antidepressant augmentation therapy, over a two-year follow-up period.