The word “genocide” was coined by Raphael Lemkin – like Arendt, a refugee from the Nazis. Lemkin was convinced that the destruction of an entire people is a unique crime, over and above the mass destruction of the individuals who make up that people. His reason was that each people makes its own contribution to universal civilization. For Arendt, by contrast, there is no such thing as a universal civilization; what makes genocide unique is its attack on the diversity of peoples, which she calls a crime against the human status. This chapter begins by discussing Lemkin’s career and thought. It criticizes his “civilization” theory, and the critique sets the stage for discussing Arendt’s theory. One philosophical puzzle is that in The Human Condition, Arendt’s concept of plurality refers to the manyness of individuals, not of peoples or other groups. The chapter explains why the diversity of groups as well as individuals matters to Arendt.