Comparative criminology has an ever more important role in the discipline, and relevance for international and national crime and justice policies. International organisations increasingly use evidence from comparative research for long-term strategic goals and policy recommendations, such as, e.g. the impact of poverty on child mortality, of inequality or simply the ‘youth bulge’ on violence levels in societies, or of traditional values on corruption. Can comparative and macro-level criminological research provide an evidence base for global crime and justice policies akin to and equivalent to the ‘gold standard’ of experimental methods on national and local levels? Other disciplines, in particular comparative political science, or development studies have produced exemplary research demonstrating the usage and usefulness of comparative studies for policy making, evaluation, transfer and policy learning. This chapter discusses the potential of comparative criminological research for enhancing the pool of evidence-based crime and justice policies, and recommends strategies for harnessing them for policy making and transfer on a global scale.