A diagnosis - the label we give to a disease - is supposed to offer certainty: a system for classifying and treating sickness, valid across time and space, and uncomplicated by value judgements or monetary concerns. Yet, as Jules Montague knows from years of working with patients in several countries, the practice is tainted by the forces of imperialism, politics, discrimination and Big Pharma. At their worst, diagnostic labels can do active harm to patients. Drawing on meticulous research and deep personal insight, Montague delves into historical diagnoses that have become extinct, and into modern maladies - from PTSD to oppositional defiant disorder to excited delirium - and explores whether they too may prove not to be true diagnostic labels at all. Eye-opening and urgent, the book reveals heart-breaking, thought-provoking stories of real people living and dying in the shadow of their diagnoses.