Depression is a serious illness that can interfere with a person's ability to work, study, sleep, eat, and enjoy activities that once were pleasurable. It is characterized by several symptoms, such as the following: persistent sad, anxious, or "empty" mood; feelings of hopelessness or pessimism; and feelings of guilt, worthlessness, or helplessness. If left untreated, depression symptoms can last for years, and may worsen as time goes on. Even with treatment, however, it is possible for depression to recur. Remission is a main goal in the treatment of depression and it may be accomplished through various strategies. This study will evaluate the effectiveness of five combinations of treatments, including medication therapy and psychotherapy, in maintaining remission of depression symptoms.