This chapter introduces Sartori’s writings on Marx, which are almost forgotten today. Sartori’s critical analysis of Marxism was both conventional and innovative. Sartori’s most original contribution to political theory may be the insight that Marxism, in its essence, is not an egalitarian but a libertarian ideology. Sartori considered Marxism not an ideology of equality but an ideology of liberty, though one often mistakenly defined and understood. Marx’s cry for an alternative democracy and his vision of the definitive triumph of liberty that will bring about the ideal society and the end of history establishes an essential link between him and Rousseau. Sartori considered Rousseau to be Marx’s progenitor. While Rousseau may be the patron of those who aspire to supersede liberal democracy, Marx is the hero of those who reject liberal democracy altogether. Sartori points out that both inspire their followers from far-reaching libertarian positions.