This book is the first comprehensive study of rare disorders from a historical, political, and social perspective. It is estimated that around 300 million people worldwide live with a rare disorder today. What do patients and associations concerned by one of the 7,000 known rare diseases have in common, and what does rarity mean to them? How did rare disorders become a mainstream category in public health policy? To answer these questions, Caroline Huyard traces the history, over more than 50 years, of medical treatments for one particular disease, and that of the orphan drug status in the United States and in Europe. The book shows that public authorities had a much greater role than biomedicine in turning rare disorders into a public health problem. A comparison of patients' experiences of 6 rare diseases as well as the activities of 8 associations in France underlines the importance of isolation and care for patients on the one hand, and the role of stakeholders' participation for associations on the other hand. This book is essential reading for researchers and students interested in contemporary healthcare systems and topics related to public policies on emerging issues, the industrialisation and regulation of medicine, the concept of care, and the governance of patient organisations.