Time is inherently present in empirical research on institutional change - most studies sequence actions and events across stages of development, over time. Yet, research has overlooked how temporality, as a negotiated organizing of time, shapes institutional processes, despite that timing, duration, and tenor of relationships are their foundational elements. To unpack the role of temporality in institutions, we examine how actors engage in temporal institutional work - that is, how they construct, navigate, and capitalize on timing norms in their attempts to change institutions. We draw on an inductive study of an institutional project to establish a novel foundation-based university that subsequently came to pace major statewide university reform. We identify three forms of temporal institutional work: entraining - as a top-down, routinized, reproductive form - and constructing urgency, and enacting momentum - both as bottom-up, issue-driven and generative forms. We show that by engaging in these types of work, actors produce windows of opportunity, synchronicity, and irreversibility as shared beliefs about temporality. These beliefs, in turn, shape how the wider institutional change unfolds. Our study shows that temporal institutional work enables institutional change. We discuss the implications for reconceptualizing institutional research from a temporal perspective.