In a predominately urban world, cities represent a significant challenge but also a unique opportunity for addressing the majority of twenty-first century global issues. Cities and city leaders bridge localized pressures and the increasing need to implement more globally focused policy agendas and now participate in a semi-formalized architecture of “global urban governance.” This chapter contends that for scholars of global governance, understanding the ways that the locus of political agency is shifting toward urban settlements is crucial for a holistic appreciation of the way that the world is governed. It also argues that quasi-localized policy responses have progressively become one of the most effective methods of addressing global governance challenges.