This chapter focuses on a member of a much larger family of interventions known as cognitive behavior therapy (CBT). Cognitive therapy (CT) was first developed as a time-limited treatment of depression. Dysfunctional cognitions about medication can be modified with CT, and behavioral interventions, such as reminder systems and behavioral plans to overcome obstacles to adherence, can be used. The efficacy of CT has been subjected to hundreds of controlled investigations across a wide range of disorders. CT is the most exhaustively studied psychosocial intervention for depressive disorders. The primary analyses of six subsequent studies, all making greater efforts to ensure that pharmacotherapy was adequately administered, found CT and pharmacotherapy to be comparably effective across 12-16 weeks. It is noteworthy that the two most recent studies used selective serotonin reuptake inhibitors and, hence, have greater generalizability to contemporary practice.