Previously published studies present conflicting conclusions about the growth of small, premature infants. To provide further data on these infants, a well-defined group of 86 premature infants appropriate for gestational age, weighing less than 1501 gm at birth, was observed until 12 months after their expected dates of delivery. Length, weight, and head circumference were measured at one, three, six, nine, and 12 months postterm. At 12 months postterm, infants were evaluated by neurologic examination and the Bayley Scales of Infant Development. Premature infants with mean Bayley scores greater than or equal to 85 were found to be significantly larger than infants with mean Bayley scores less than 85 by three months postterm. Birthweight, gestational age, duration of hospitalization in the neonatal intensive care unit, pneumonia, hypoglycemia, perinatal neurologic impairment, acidosis, and hypoxemia were found to be associated with reduced growth at one year. Conflicting results in previous studies may be a result of failure to separate infants with good neurobehavioral outcome from those with poor outcome.