When international courts are given sweeping powers, why would they ever refuse to use them? The book explains how and when courts employ strategies for institutional survival and resilience: forbearance and audacity, which help them adjust their sovereignty costs to pre-empt and mitigate backlash and political pushback. By systematically analysing almost 2,300 judgements from the European Court of Human Rights from 1967-2016, Ezgi Yildiz traces how these strategies shaped the norm against torture and inhumane or degrading treatment. With expert interviews and a nuanced combination of social science and legal methods, Yildiz innovatively demonstrates what the norm entails, and when and how its contents changed over time. Exploring issues central to public international law and international relations, this interdisciplinary study makes a timely intervention in the debate on international courts, international norms, and legal change. This book is available as Open Access on Cambridge Core.