Although antidepressants have helped millions worldwide, a substantial proportion of patients fail to respond or remit. There is little published information available to clinicians for diagnosis and management of treatment-resistant depression, causing them to make difficult decisions regarding treatment options with very limited data. The editors and their internationally distinguished team of contributors have set out to address this problem, giving a critical assessment of all aspects of treatment-resistant depression: causes, epidemiology, comorbidity, evaluation, and treatment. This timely book will be invaluable to clinicians, neuroscientists, researchers, and graduate students.