In this essay, I propose a mutually constructive reading of the work of Jacques Rancière and Jean-Paul Sartre. On the one hand, I argue that Rancière's egalitarian political thought owes several important conceptual debts to Sartre's Being and Nothingness, especially in his use of the concepts of freedom, contingency and facticity. These concepts play a dual role in Rancière's thought. First, he appropriates them to show how the formation of subjectivity through freedom is a dynamic that introduces new ways of speaking, being and doing, instead of being a mode of assuming an established identity. Second, Rancière uses these concepts to demonstrate the contingency of any situation or social order, a contingency that is the possibility of egalitarian praxis. On the other hand, I also argue that reading Sartre with Rancière makes possible the reconstruction of Sartre's project within the horizon of freedom and equality rather than that of authenticity.