This chapter considers the central role of uncertainty for cognition and action in construction project organising with a focus on how project practitioners think about the future. It takes a cognitive approach to uncertainty in the context of a broader information processing approach to decision-making in organisations. The chapter’s main concern is the failure of this approach to connect cognition through to action. The chapter presents the UnCoCoH (Un-Certain Complex Complicated Hidden) model as a tool to assist in recognising the transition from individual cognition to collective action. It also highlights the role of narratives for stabilising uncertainty through this transition. This provides a foundation for working towards the development of a projectivity perspective in construction project organising and advancing a research agenda for this program of research.