What’s the best way to help disadvantaged children reach their potential? What do they need to succeed in school, in work and in a family? How can they receive the necessary building blocks for a happy and productive life, one free of poverty? For policymakers and development experts, the answers lie in early childhood development, when children’s brains and bodies are still developing. Proper healthcare, nutrition, psychosocial stimulation, and emotional support all play a role in giving children the foundation they need to do well later on. But what happens after? Do programs designed to bolster disadvantaged children’s cognitive, emotional and physical development really help over the long term? Or are gains seen in the early years lost by adulthood? The World Bank is focused on developing and supporting programs that help children reach their potential and live lives free of poverty. To help build a body of evidence of what works, the World Bank financed an evaluation of a program in Jamaica that targeted mothers of babies stunted due to malnutrition. The mothers received either support and guidance on how to encourage their babies’ development through play and language, or nutritional supplements, or a combination of the two. Twenty years later, the evaluation found that children who received the extra stimulation, whether with nutritional supplements or not, were earning more money than similarly stunted babies whose mothers received just nutritional supplements or no intervention. The children whose mothers had received the extra guidance also were doing as well financially as the less disadvantaged (and non-stunted) children. This study, a rare look at the effects of early childhood intervention over the decades, gives policymakers and development experts tangible proof of the potential effects of early childhood development programs.