Genocide is defined in international law as the intent to destroy one of four protected groups: racial, national, ethnic, or religious. Genocide is considered morally unique as a wrong, and as the most serious of all international crimes. I will critically assess the conceptual and normative underpinnings of this “crime of crimes.” My view is that genocide should not be seen as morally unique and significantly worse legally than other serious international crimes. As genocide's status changes, its scope should also be expanded, most especially to allow for cultural genocide and ethnic cleansing to be counted as crimes of genocide. And the list of protected groups should be expanded from the current group to include gender and even political groups. I will defend such a reconceptualization of genocide in international law, and will do so by focusing on actual legal cases of genocide, with special attention to the Rwandan genocide. But even if my modest changes are not accepted, my hope is that this volume will stir debate about how best to think of the crime of genocide. In one of my previous books, Crimes Against Humanity: A Normative Account, I included a chapter on genocide. In the current volume I provide the full defense of the view that I had sketched, and I also explain why I think in the end that genocide should be thought of not as the crime of crimes but as one of, if not the most important, crimes against humanity.