This thesis explores Arendt’s theory of action, taking inspiration from recent secondary literature to explore the tension between an expressive model of action and a communicative model of action. The expressive model is primarily concerned with the disclosure of the actor through deeds and words, and corresponds most to the human condition of plurality. The communicative model aims to establish relations of solidarity, and relies on the condition of worldliness. Secondly, the way in which the two models of action fit chronologically into Arendt’s analysis of totalitarianism is explored. It is argued that the elements which prefigure totalitarianism proper – the decay of the nation-state, racism and antisemitism – eliminate the conditions for communicative action. The emergence of totalitarianism leads to the destruction of the condition of plurality, the prerequisite of expressive action. It is argued that both models of action need to be viewed as a response to this central political phenomenon of totalitarianism.