More-educated women have fewer children. This seemingly straightforward relationship is actually complex, and the benefits associated with different levels of education can vary considerably by setting. This policy brief describes adolescent girls’ reproductive health risks and how increasing their educational attainment reduces those risks, including early and unwanted fertility, and benefits their future families and society. This brief also highlights some factors that contribute to this powerful education-fertility dynamic. Many successful programs are keeping adolescent girls in school and many programs offer reproductive health information and services out of school, including family planning. Combining such programs may yield more benefits than either one alone.