The great international problems of our time beggar the imagination: global warming, pandemics, war crimes, nuclear proliferation, just to name a few. Their complexity confounds the most agile of technocrats, and the stakes involved are high, affecting billions of people living under every sort of government. For half a century, the conventional approach to these problems has been to build massive international treaties. Intricate worldwide problems demand an integrated approach—a grand bargain, so to speak, that addresses all the winners and losers in a single, encompassing agreement. But what if this approach results in less progress?