RESUMEN
At the inception of the Eunice Kennedy Shriver National Institute of Child Health and Development Neonatal Research Network (NRN), provision of care for extremely preterm (EPT) infants was considered experimental. The NRN Follow-up Study Group, initiated in 1993, developed infrastructure with certification processes and standards, allowing the NRN to assess 2-year outcomes for EPT and to provide important metrics for randomized clinical trials. This chapter will review the NRN Follow-up Study Group's contributions to understanding factors related to improved neurodevelopmental, behavioral, and social-emotional outcomes of EPT infants. We will also discuss follow up challenges, including reassessing which outcomes are most meaningful for parents and investigators. Finally, we will explore how outcome studies have informed clinical decisions and ethical considerations, given limitations of prediction of complex later childhood outcomes from early neurodevelopmental findings.