This first chapter sketches a brief conceptual history of reparations in international criminal justice and introduces some key concepts and terms used throughout the book. Chapter 1 shows how questions of justice in response to mass atrocities have been informed by two international normative demands: the ‘fight against impunity’ and the corresponding rise of international criminal justice; and the emergence of international human rights and the increasing attention paid to victims of crimes. These two main normative responses – punishment of perpetrators and redress for victims – gradually converged over time, laying the ground for the emergence of reparations mandates at international(-ised) criminal courts. That this was not a linear development is demonstrated by interrogating the absence of reparations at the two ad hoc international criminal tribunals, the International Criminal Tribunal for the former Yugoslavia (ICTY) and the International Criminal Tribunal for Rwanda (ICTR).