Child marriage in developing countries remains pervasive. One-third of girls are married before age 18. That’s 39,000 girls each day, with 1 in 9 marrying before age 15. Among countries with the highest prevalence of child marriage, girls with three years of schooling or less are up to six times more likely to marry young than girls with secondary education. The causality runs both ways: child marriage reduces educational attainment, and, conversely, girls with less access to quality education are more likely to marry early.