Major Depressive Disorder (MDD) is one of the most prevalent psychiatric disorders, with a lifetime prevalence rate of roughly 20%. MDD is a leading cause of disability and premature death worldwide, leads to greater impairment in work functioning than other chronic medical conditions, and has an estimated annual cost of $210 billion in the US. The proposed text is designed for mental health professionals and will present state-of-the-art treatment options that are used in the Depression Clinical and Research Program (DCRP) at the Massachusetts General Hospital. The text provides different treatment options so that providers can `think outside the box' of conventional interventions. The introductory sections discuss general themes about diagnosing and treating depression. The major body of the book, however, consists of chapters organized under the topics of new medication, new psychotherapy, alternative treatments, and consideration of specific populations and how to modify interventions to best treat these patients. Each chapter begins with a case vignette to illustrate key characteristics of the disorder process or treatment and reviews the history, research support, and new advances of these topics. In addition, the chapters include a description of how to apply this topic in treatment and frequently asked questions and answers. This book will be a unique contribution to the field. Existing guides focus on individual treatments of Depression, or include brief descriptions of interventions as a whole. The DCRP has consistently been a forerunner of clinical treatments for depression and often treats challenging cases of this disorder. This book will provide a practical and useful resource with wide applicability.