Given the benefits of early childhood education, many countries try to ensure universal accessibility to early childhood education. However, with their limited budgets and chronic poverty, least developed countries face a huge disadvantage in providing access to early childhood education, especially for children of lower income families and those living in remote areas. This study aims to determine how accessibility to early childhood education and child development affects cognitive, learning, physical, and social-emotional readiness. We use nationally representative data from the Lao Social Indicator Survey (LSIS) for a case study of Lao PDR, which is representative of least-developed countries. Our estimation indicates that mother's educational attainment and economic status of the family have an important impact on children's preschool enrollment. In terms of children's development, receiving early childhood education is likely to play a significant role in developing cognitive skills. Furthermore, in addition to early childhood education per se, activities associated such education also play an important role in fostering children's development. Hence, early childhood education should be promoted in order to enhance all children's access to preschools and thus ensure that their development remains on track.