The spatial dimensions of water management heavily rely on accurate hydrological estimates in the landscape. This has exactly been the focus of the Predictions in Ungauged Basins (PUB) initiative of the IAHS. The initiative has significantly advanced the science by furthering process understanding and estimation methods, and by synthesising the knowledge across processes, places and scales. Ongoing research on PUB is increasingly treating water management as an intrinsic part of the hydrological cycle and is developing processes understanding and methods to account for the feedbacks between humans and water in the landscape.