Almost three decades after Leo Strauss’s death, Nasser Behnegar offers the first sustained exposition of what Strauss was best known for: his radical critique of contemporary social science - particularly of political science. Behnegar argues that Strauss was not averse to the scientific study of politics, but he did reject the idea that it could be built upon political science’s cursory distinction between facts and values. Max Weber was, for Strauss, the most profound exponent of values relativism in social science, and Behnegar’s explication artfully illuminates Strauss’s critique of Weber’s belief in the ultimate insolubility of all value conflicts. As Behnegar shows, values - the ethical component lacking in contemporary social science - are essential to Strauss’s project of constructing a genuinely scientific study of politics.