Children and young people who go missing from out-of-home care placement are among the most vulnerable in Australia, yet there has been limited population-level evidence to inform policy responses. As New South Wales (NSW) continues to reform and rebuild its out-of-home care system, including the recent inquiry launched by the NSW Ombudsman into children and young people away from placement, this data is critical to inform evidence-informed service delivery and to improve the safety, welfare and wellbeing of these young people. Authored by researchers from the University of Sydney, the report provides the first linked, population-scale analysis of children who spend time away from their placement in NSW and identifies practical opportunities to strengthen prevention, intervention and support. The report draws on linked administrative records from the NSW Human Services Dataset to examine the prevalence, risk factors and service use patterns of children who spent time away from placement between 2000 and 2019.