International Organizations (IOs) promote and diffuse norms within world politics. This prompts the question: where do these norms come from? This inquiry analyses how IOs have been perceived within the emerging norms literature where IOs are 'norm diffusers' within the international system, and finds that the way in which IOs themselves internalize norms has not been taken into account. This poses a potentially fruitful new avenue of inquiry into why and when IOs behave as norm diffusers. An interpretation of when and why IOs internalize norms is offered by positing that IO identities are not fixed and that they are 'norm consumers' socialized by state and non-state actors.