Practitioners implementing urban climate initiatives are frequently faced with the intermittent nature of urban projects and the short-termism of policy experiments. In this conjuncture, understanding how urban transformations are advanced necessitates grasping how small-scale efforts are carried forward or sustained despite these brief time horizons and a related condition of resource scarcity that urban bureaucracies also confront. To address this question, this article develops a figure we provisionally term the chainmaker. Building on literature that discusses the role of intermediaries in debates on entrepreneurial governance and urban experimentation, this heuristic captures the role of urban practitioners who build temporal chains, that is, who sustain ideas, projects or reforms across different initiatives and bureaucratic cycles in the long run. We draw on a comparative study that traced the functioning of these initiatives in four secondary cities in Mexico and India to explore two different dimensions of intermediation over time. This work of anchoring and sustaining small-scale policy efforts to effect lasting change reveals the challenges to creating continuity and effecting structural change and the different conditions of that work in the studied contexts.