We have studied neonatal and late mortality rates among children with a birthweight of less than 1.501 grams. The sample consisted of children admitted to the neonatal intensive care unit at the Dept. of Pediatrics in Trondheim during 1985 and 1986. 58 children were admitted, three of whom had lethal malformations (two triploids, one trisomi 18). Of the remaining 55 children, 12 died in the neonatal period. This gives a neonatal mortality rate of 21.8%, which is comparable with the results reported from other centers. However, six children died after the neonatal period, giving a late mortality rate of 10.9%. This is higher than reported in the literature. Most reports that we have been able to find are six to ten years old, and at that time the neonatal mortality rates were significantly higher. Five of the six children who died late had bronchopulmonary dysplasia. The sixth child suffered a sudden infant death. The incidence of bronchopulmonary dysplasia was 27.2%, which is comparable with the incidence reported in the literature. The present study clearly shows the importance of taking late mortality rates into consideration when evaluating neonatal care.