The mood disorders (major depressive disorder, bipolar disorder, and dysthymia) are a significant public health issue: mood disorders affect approximately one in four people during their lives; in total, over 8 million Canadians are affected by mood disorders, costing the economy over $6 billion annually. Mood disorders are generally recurrent: approximately 50% of cases of major depressive disorder will relapse at least once; 15% will run a chronic course. With bipolar disorder, a chronic course of episodes of depression and/or mania intermixed with episodes of normal mood is typical. At Sunnybrook (SHSC), 75% of inpatient mental health admissions are due to mood disorders. Clinically, with mood disorders, earlier recognition of symptom changes in patients provides greater potential for early intervention and suppression of relapses, which in turn leads to reduced outpatient resource utilization, fewer Emergency Department visits, and fewer readmissions.