Under what conditions can we expect international courts to be progressive? The introduction begins with a discussion of why it is compelling to answer this question by looking at the case of the European Court of Human Rights – a court that is not unambiguously progressive. It then lays out the theoretical and empirical foundations of the book, presenting the key concepts of forbearance and audacity – strategies that courts employ to adjust their sovereignty costs while maintaining a good institutional reputation. The theoretical framework explains why the Court needs to oscillate between forbearance and audacity, and how this oscillation has shaped the norm against torture and inhuman or degrading treatment. The empirical analysis, in its turn, combines social science methods and legal analysis to reveal the extent to which the Court has resorted to forbearance and audacity when interpreting the norm against torture and inhuman or degrading treatment, and how such episodes influenced the norm’s developmental trajectory. The introduction concludes by explaining the determinants of forbearance and audacity and putting forth the book’s key contributions to the existing debates.