Patients will be recruited through Family Physicians, and referrals to the Mood Disorders Program. We will respond to referrals with a brief telephone screening interview, and appropriate referrals will be prior to the initiation of medication. Study patients will be treated according to clinic practice guidelines for major depressive disorder and bipolar disorder, as well as for comorbid psychiatric conditions. At intake, a variety of measures will be used to collect data on symptoms and co-morbidity, cognitive processing, social functioning, family and personal history, life events, substance use, mood symptoms, personality functioning and characteristics, and physical well-being (baseline blood work and urine, heart rate, blood pressure, weight).