Sleep matters to those who care for young children. The duration and timing of sleep can have a profound effect on a young child’s everyday behaviour, learning and health and also has a significant impact on the routines and wellbeing of the adults who provide his or her care . Yet there is surprisingly little evidence regarding the developmental function of early sleep patterning to guide care practice. Current understanding of the processes underpinning the normative transition from multiple sleep wake cycles seen in infancy (polyphasic sleep) through to consolidation of sleep into a single night period (monophasic sleep) is limited. Age at cessation of napping occurs anywhere between age 1 and 5 years but we do not know whether this timing holds significance for long–term behavior, learning and health. Care practices almost certainly influence this timing but we do not understand in what way or to what effect. Understanding the developmental meaning of changing sleep patterns, the association of individual sleep patterns with variation in care environments and the pathway from these to long-term child outcomes are all necessary steps in identifying appropriate care. This knowledge will inform policy and practice in childcare settings where management of sleep is an issue of controversy and also inform parenting practice where early child sleep behaviours can have a major impact on family functiioning, parent wellbeing and child development