Mood disorders are one of the greatest causes of disability in the community. Both major depressive disorder and bipolar disorder usually start during adolescence and early adulthood, and frequently recur, causing suffering and disability over a large part of the lifespan. Our firstline treatments for mood disorders – psychotherapy and medication – are helpful for many patients, but many do not get the help from them they need. Our research seeks to find new treatments, and new treatment approaches, for mood disorders. We are studying new treatments in clinical trials, and using functional MRI to understand how they work, and which patients they help. We are also using functional MRI to help us better understand the disorders themselves.