Our goals are 1) to use functional magnetic resonance imaging (fMRI) to predict which depressed individuals will respond to different validated treatments for unipolar depression including Cognitive Therapy (CT) and antidepressant medications (selective serotonin reuptake inhibitors; SSRIs) and 2) to understand whether CT and SSRIs affect similar aspects of brain function underlying cognition and emotion. Thus, we will examine depressed adults ages 18-55 using fMRI during cognitive and emotional information processing tasks, before and after treatment with an SSRI (n=25) or CT (n=40). We hypothesize that: 1) Recovery will occur in treatment with an SSRI primarily for individuals with increased reactivity in limbic brain regions associated with emotion generation and prefrontal regions associated with regulation,. 2) Recovery with CT will occur for patients with increased activity in brain regions associated with emotion generation but decreased activity in prefrontal regions associated with emotion regulation. 3) Recovery with an SSRI will yield similar changes in brain function to CT in brain regions associated with emotion generation but less change in brain regions responsible for emotion regulation such as the prefrontal cortex. Findings from this study may have a profound impact on reducing the burden of clinical depression by providing evidenced-based diagnostic and treatment guidelines.