PROJECT SUMMARY The Eunice Kennedy Shriver NICHD cooperative multicenter Neonatal Research Network (NRN) is committed to providing a strong scientific evidence base for the care of sick and preterm newborns to promote healthy outcomes. Since 2011, the University of Pennsylvania Perelman School of Medicine (Penn) and Children’s Hospital of Philadelphia (CHOP) Clinical Center has been making significant contributions to all aspects of NRN research. Our Clinical Center includes three large level three neonatal intensive care units in academic perinatal centers, one large level four unit in a children’s hospital, and three follow-up clinics, all of which are unified under the leadership of the Penn/CHOP Division of Neonatology. We are a leading NRN Clinical Center for recruitment, retention, and study follow-up. We rank #3 among the 15 current Clinical Centers for number of infants recruited into the five currently ongoing randomized trials. Penn/CHOP 2-year follow-up rates are consistently higher than NRN average follow-up rates. Since we joined the NRN, we have conducted follow-up visits at 18-26 months corrected age in 98.5% (385 of 391) of Penn/CHOP study participants enrolled in 9 clinical trials. Our investigators and coordinators provide important leadership within the NRN, serving on multiple subcommittees and facilitating startup of new centers through the NRN Open Network mechanism. Our Principal Investigator leads two large school-age follow-up studies of NRN trials and Penn/CHOP investigators have published 27 NRN manuscripts as first or senior author since our last competitive renewal. We also provide unique contributions through our team’s expertise in innovative epidemiological techniques and health disparities. We are fully prepared to continue our robust participation in the NRN by contributing our team’s special strengths in clinical research methodology, collaborating as collegial and productive partners in ongoing studies, and introducing innovative new protocols to advance the scientific mission of the NICHD NRN in the next award cycle.