Perinatal mortality in very preterm infants has decreased by up to 50% during the last decades. Studies of changes of long-term outcome are inconclusive. We studied the visual, auditory, neuromotor, cognitive and behavioural development of two geographically defined populations of very preterm, singleton infants, born in 1983 and in 1993, and analysed the relationship between perinatal risk factors and outcomes. The incidence of disabling cerebral palsy increased from 6.0% to 11.1% (OR 2.45 [95% CI 1.11, 5.38]). Impaired vision and strabismus decreased significantly, presumably by continuous monitoring of pO2. Hearing problems, the need for special education and the incidence of behavioural problems did not change over time. The proportion of children who showed optimal performance in every developmental domain increased from 29.5% in 1983 to 43.2% in 1993. Cerebral palsy was associated with male gender in 1983, with low Apgar score and intraventricular haemorrhage in 1993, and with seizures both in 1983 and in 1993. The intensiveness of neonatal treatment has increased, leading to the survival of many more healthy infants, but at the cost of more infants with cerebral damage. Modern perinatal care is no longer limited by the devastating effects of pulmonary problems as it was in the past, but fails to safeguard cerebral integrity in very preterm infants. © 2007 The Authors.