This article exposes the fact that the Rwandan genocide and its aftermath has many lessons for African leaders, especially that modern international criminal law is committed to punishing perpetrators of heinous crimes. The Arusha-based International Criminal Tribunal for Rwanda (ICTR) has also operated a successful jurisprudence that has immensely contributed to the development of modern international law. The article looks at the historical context of the genocide, the jurisprudence and case law of the ICTR, the novel concepts that have contributed to the growth of international law, and the significance of rebuilding a post-genocide Rwanda.