Scholars have devoted considerable attention to the informational role of international institutions. However, several questions about the informational aspects of institutional behavior remain underexplored: What determines how audiences respond to institutional decisions? Through what channels does information provision affect foreign policy? To answer these questions, I develop a formal model motivated by recent literature on the informational effects of security institutions. The formal model depicts information transmission between a domestic audience, an international institution, and a foreign policy maker. Statements issued by member states through the institution serve to inform the audience about the likely outcomes of its leader's actions. The model demonstrates that leaders have incentives to consult relatively conservative institutions, because their support convinces audiences that they should also support proposed policies. Leaders face incentives to avoid the disapproval of more revisionist institutions, because their opposition will tend to induce public opposition. The empirical implications are discussed. (Contains 3 figures and 34 notes.)