BACKGROUND Pulmonary interstitial fibrosis in children is a disease of unknown aetiology, usually associated with a poor prognosis. METHODS In this case series we describe 11 children presenting over a 10 year period, managed conservatively and associated with a good prognosis. RESULTS In six, symptoms were present from birth and 10 had symptoms at or before 3 months. Diagnosis was made using chest computed tomography and percutaneous lung biopsy. All patients were treated with oral prednisolone. In five no steroid response was noted. One patient responded to hydroxychloroquine. Home oxygen was required in five patients. At follow up all patients are alive at a median age of 6 years (range 1 to 12 years). The two recently diagnosed children have significant symptoms, seven have dyspnoea on exercise, and two are symptom free. CONCLUSION The good prognosis seen in these patients is different to previous case reports, indicating a greater than 50% mortality.