In the introduction to this roundtable, we argue that global governance currently faces hard times because it is affected by a set of significant developments revolving around the changing distribution of state power, the rise of nationalist populism, and the frequent occurrence of transnational crises, while seeking to facilitate collective action on complex cooperation problems. Against this backdrop, the essay identifies two major institutional dynamics of global governance in hard times: first, the drift of formal intergovernmental organizations (FIGOs) that is caused by them being gridlocked in a period of significant changes in their social, (geo)political, economic, and technological environment. Second, the proliferation of various types of low-cost institutions. To help us think systematically about how these two interrelated institutional dynamics affect global governance, the essay develops the innovation thesis and the decline thesis. The “innovation thesis” suggests that by transitioning from a rather exclusive and hierarchical system revolving around FIGOs into a more inclusive and heterarchical system revolving around institutional diversity, global governance is currently being adapted to its new environment. The “decline thesis,” by contrast, argues that the two institutional dynamics undermine rules-based multilateralism and may lead to a shift back toward traditional (great) power politics that does not respect institutional constraints.