This introduction proposes a conceptual framework for analysing the governance of urban diversity, which places agency at the center. We explore how a wide array of urban actors, namely urban leaders, migrants, and civil society groups, shape the politics of diversity governance in cities. Rejecting static, top-down models, we conceptualize diversity governance as a dynamic, multiscalar, and contested process, unfolding through spatial transformations, policy innovations, and transnational circulations. By framing these processes through the notion of “city makers,” we emphasize the roles of both powerful elites and marginalized actors in shaping inclusive or exclusionary urban futures. Drawing from empirical case studies in cities such as Paris, Singapore, Guangzhou, and Hamamatsu, the book advances a comparative, process-oriented, and actor-centered approach to diversity governance, highlighting how the intersecting efforts of various city makers co-produce contemporary urban diversity governance.