Which groups do global governance institutions address in their efforts to legitimate themselves? Global governance institutions are increasingly attempting to present themselves as legitimate vis-à-vis both internal and external audiences. Yet, empirical research on these legitimation audiences is still nascent. This article proposes a conceptual framework that highlights the selection of audiences by global governance institutions as a key element of their self-legitimation. Specifically, we argue that our approach addresses three continuing challenges in empirical research on self-legitimation. First, it emphasises how different actors within the institution may pursue multiple, and potentially conflicting, strategies with regard to the legitimation audiences they address. Second, our framework calls attention to what we call intermediary legitimation audiences, that is, audiences targeted with the expectation that they will in turn convince other audiences of the institution’s legitimacy. Finally, instead of taking for granted that external critique steers who is targeted by self-legitimation, our approach highlights that an institution’s internal assessment of such critique is decisive. We demonstrate the wide applicability of our framework through exploratory studies of three global governance institutions that differ with regard to their membership compositions: the World Health Organization, the International Criminal Court and the Forest Stewardship Council.