This study examines the effects of universal Early Childhood Education and Care (ECEC) on child development and children's later life outcomes. Using meta-analytical techniques, we synthesize the findings from recent studies that exploit natural experiments to identify the causal effects of universal ECEC arrangements. We use 250 estimates from 30 studies conducted between 2005 and 2017. Our meta-regressions include estimates on a wide variety of children's outcomes, ranging from (non-)cognitive development measured during early childhood to educational outcomes and earnings in adulthood. Overall, the evidence on universal ECEC is mixed. Age of enrollment is not a major factor in explaining the impact. Some evidence indicates that more intensive programs produce more favorable outcomes. Program quality matters critically: high quality arrangements consistently generate positive child outcomes. Publicly provided programs produce more favorable effects than privately provided (and mixed) programs. Furthermore, there is no evidence of fading out. The gains of ECEC are concentrated within children from lower socioeconomic families. (author abstract)