Michael Zürn's Theory of Global Governance is an original, bold, and compelling argument regarding the causes of change in global governance. A core argument is that legitimation problems trigger changes in global governance. This contribution addresses two core features of the argument. Although I am persuaded that legitimacy matters, there are times when: legitimacy appears to be given too much credit to the relative neglect of other factors; other times when the lack of legitimacy has little discernible impact on the working of global governance; and unanswered questions about how the legitimacy of global governance relates to the legitimacy of the international order of which it is a part. The second feature is what counts as change in global governance. Zürn reduces change to either deepening or decline, overlooking the possible how of global governance. In contrast to Zürn's map of global governance that is dominated by hierarchies in the form of international organizations, an alternative map locates multiple modes of governance: hierarchies, markets, and networks. The kinds of legitimation problems that Zürn identifies, I argue, can help explain some of the movement from hierarchical to other modes of global governance.