Four years after The Lancet published a first Series on early child development, the challenge of supporting 200 million children under five years to reach their developmental potential remains. A new Series of two papers and a Comment now documents progress worldwide. The Series aims to identify gaps in implementation and coverage of interventions, calculate the economic costs of missed investment in early learning programmes, and present new evidence on the causes and effects of developmental inequities in early childhood.
The first article looks at the evidence on risks and protective factors in early child development, and identifies new risks not previously described. The second looks at the effectiveness of early child development intervention programmes in low-income and middle-income countries, as well as the cost of not investing in early child development.
The authors conclude that early childhood is the most effective time to prevent inequalities before disparities widen, particularly for the poorest children. By investing in children in early childhood, there are lifetime consequences not only for individuals but for the wellbeing of societies. Rapid action must now follow to ensure that effective interventions are financed and integrated into programmes that aim to improve maternal and child health outcomes.