We previously reported on a series of 27 newborn infants treated for posthemorrhagic hydrocephalus with external ventricular drainage during 1984 to 1989. In the present study we continued to evaluate this technique during the subsequent 8 years (37 patients; mean birthweight 1251+/-478 g; mean gestational age 29+/-2.9 weeks; 51 drains), and we now report on the long-term experience with this method, complications, and neurodevelopmental outcome of the survivors. The mean age at drain insertion was 21 days, and the mean duration of drainage 23 days. Eight infants died of causes unrelated to external ventricular drainage. Eleven of the survivors did not require a permanent shunt. Two patients experienced ventriculitis, resulting in an infection rate of 5.4% per patient and 3.9% per drain. The neurodevelopmental outcome was mainly dependent on the extent of the pre-existing parenchymal injury. We conclude that external ventricular drainage is a safe and effective technique for the management of preterm infants with posthemorrhagic hydrocephalus.