Policy discussions to ameliorate socioeconomic (SES) inequalities are increasingly focused
on investments in early childhood. Yet such interventions are costly to implement, and clear
evidence on the optimal time to intervene to yield a high economic and social return in the
future is meagre. The majority of successful early childhood interventions start in the
preschool years. However socioeconomic gradients in cognitive skills, socio-emotional
functioning and health can be observed by age three, suggesting that preventative
programmes starting earlier in childhood may be even more effective. We discuss the
optimal timing of early childhood intervention with reference to recent research in
developmental neuroscience. We motivate the need for early intervention by providing an
overview of the impact of adverse risk factors during the antenatal and early childhood
periods on outcomes later in life. We provide a brief review of the economic rationale for
investing early in life and propose the ‘‘antenatal investment hypothesis’’. We conclude by
discussing a suite of new European interventions that will in form this optimal timing debate