Rates of survival and of neurological impairment in a geographically defined population of low birthweight infants born during 1979-1981 were determined by tracing infants and assessing survivors at pre-school age. Comparison with data from similar studies relating to earlier years shows that the proportion of low birthweight infants who survive with no major impairment has increased significantly; the risk of surviving with an impairment has not altered sufficiently for a significant difference to be apparent from these comparisons.