Educating girls is a universally accepted strategy for improving lives and advancing development. Girls' schooling is associated with many demographic outcomes, including later age at marriage or union formation, lower fertility, and better child health. However, the causal pathways between education and demographic outcomes are not well understood. To advance understanding of the relationships between girls' education and demographic outcomes and to encourage more research on the determinants, content, context, and consequences of girls' education the National Academies of Sciences, Engineering, and Medicine conducted a workshop addressing these issues on May 11 and 12, 2017. This publication briefly summarizes the presentations and discussions from the workshop.