The contexts in which societies attempt to address legacies of serious and massive human rights violations are integral to the concept of transitional justice. Such contexts vary widely: they can include ongoing conflicts, post-authoritarian transitions, post-conflict transitions, and post-transitional periods. They can also differ in terms of institutional and political fragility as well as levels of economic and social development. Transitional justice efforts, however, have sometimes been criticized as a toolkit to be applied uniformly wherever widespread human rights violations have occurred. Policymakers and practitioners are therefore called on to take context into greater consideration when advocating and designing transitional justice processes. This paper examines some of the main contextual factors that have implications for responding to massive human rights violations: the institutional context, the nature of conflict and violence, the political context, and economic and social structural problems. It presents the findings of an ICTJ research project on the challenges and opportunities of seeking accountability, acknowledgment, and reform in different—and difficult—settings.