Bronchopulmonary dysplasia (BPD), a fibrotic/emphysematous lung disorder is a common sequela among extremely premature infants. The severity of BPD, but not incidence, has been reduced by surfactant therapy. BPD remains one of the most significant contributors to excessively prolonged hospital stays and, therefore, potentially avoidable costs. Research leading to a reduction in BPD morbidity should prove cost effective in the estimated 10,400 affected infants annually (40 percent of a projected 26,000 survivors of birthweights less than 1,250 grams).