Under what conditions do officials in international organizations wield influence as informal political entrepreneurs? Two conditions, I argue in the article under discussion, must obtain: First, an asymmetry in the availability of information or ideas must impede national governments from negotiating Pareto-efficiently. High transaction costs, relative to gains, must induce a coordination failure. Actors able to provide the three essential entrepreneurial functions—initiatives, mediation, mobilization—must be scarce. Second, international officials must enjoy or be accorded privileged access to the information or ideas necessary to act as entrepreneurs and induce more efficient interstate bargains. Where either of these two conditions is absent, third-party entrepreneurial activities are likely to be redundant (because states, as stakeholders, would have greater means and incentives to act as entrepreneurs) or futile (because a consensual support among states would not be forthcoming anyway).