Intra- and periventricular haemorrhage, cystic and diffuse periventricular leucomalacia, post-haemorrhagic ventriculomegali, and cerebral atrophy are "visible" forms of brain injury and explain one third of neurodevelopmental impairment in preterm infants. We have not been successful in proving the benefits of specific preventive measures after birth. The risk of brain injury, however, has decreased over the years, possibly because understanding of the pathophysiology has led to more precisely adapted support of vital functions.