Book excerpt: Managing Treatment-Resistant Depression: Road to Novel Therapeutics defines TRD for readers, discussing the clinical and epidemiological predictors, economic burden and neurobiological factors. In addition, staging methods for treatment resistance are fully covered in this book, including serotonin specific reuptake inhibitors, serotonin norepinephrine reuptake inhibitors, other classes of antidepressants, including tricyclic antidepressants and monoamine oxidase inhibitors, augmentation strategies, and newer antidepressant treatments like ketamine and esketamine. In addition, evidence supporting the use of psychotherapies and neuromodulation strategies are also reviewed. Written by top experts in the field, this book is the first of its kind to review all methods of treatment for TRD. Defines Treatment-Resistant Depression and Staging Treatment Intensity Includes Treatment-Resistant Depression options for children, adolescents, geriatrics, during pregnancy, and during post-partum and menopause transitions Discusses the use of Ketamine and Esketamine for treatment-resistant depression