RT Journal Article SR Electronic T1 The First Thousand Days: early, integrated and evidence-based approaches to improving child health: coming to a population near you? JF Archives of Disease in Childhood JO Arch Dis Child FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP 837 OP 841 DO 10.1136/archdischild-2019-316929 VO 105 IS 9 A1 Jonathan C Darling A1 Panagiotis D Bamidis A1 Janice Burberry A1 Mary C J Rudolf YR 2020 UL http://adc.bmj.com/content/105/9/837.abstract AB The ‘First Thousand Days’ refers to the period from conception to the child’s second birthday. It is increasingly gaining traction as a concept to guide public health policy. It is seen as a crucial window of opportunity for interventions that improve child and population health. This review outlines the origin and growth of the First Thousand Days concept, and the evidence behind it, particularly in the areas of brain development and cognition; mental and emotional health; nutrition and obesity; programming and economic benefits. The review then describes UK experience of use of the concept to inform policy, and a recent government inquiry that mandates more widespread implementation.