This paper seeks to advance understanding of how new social ventures can gain legitimacy in authoritarian contexts. Through a study of a new disability rights organization in post-revolutionary Egypt, we theorize how authoritarianism poses distinct challenges for social ventures that require different legitimation strategies than those commonly reported in the literature. Specifically, we use our case study to build a theoretical model that suggests social ventures need to achieve optimal assimilation by balancing protective disguise with harmonious advocacy. By explicitly theorizing social venture legitimation in authoritarian contexts, we advance the budding literature on social venture legitimation that has so far predominantly considered legitimation in more democratic contexts. Moreover, our study shows that organizational legitimacy may need to be conceptualized differently when examining social ventures – and indeed other forms of organization – in authoritarian regimes.