We hypothesized that successful implementation of regionalized perinatal care would result in early identification and antenatal referral of high-risk neonates, and also improved stabilization before and during transport of those transferred postnatally. We conducted a retrospective study of demographic characteristics and transport outcome in two defined groups of neonates transported to regional perinatal centers in Tennessee, one group (n = 218) from the first year of regionalization (1975), and a second group (n = 261) from the 12th year (1986). The percentage of outborn infants decreased, from 50% of all admissions in 1975 to 22% in 1986 (P = .005). Likewise, the percentage of low-birthweight neonates transported after birth decreased, from 59% of all transports to 32% (P = .002). The frequency of stabilization measures performed before and during transport increased between study years (intravenous line placement: 12% to 58%, P = .0001; assisted ventilation: 10% to 33%, P = .001). The incidence of complications during transport decreased between study years (cyanosis: 25% to 8%, P = .0001; hypothermia: 30% to 3%, P = .0001; acidemia: 33% to 13%, P = .011). Both transport-related mortality and neonatal mortality decreased between study years (2.8% to 0.8%, P = .043; 17% to 7%, P = .0001, respectively). We conclude that regionalization during its first decade has been successful in improving perinatal care in Tennessee as indicated by favorable changes in referral patterns and improved outcome of transported neonates.