Antenatal diagnosis of lung abnormalities by ultrasound has been a much more frequent occurrence in recent years. There is a range of appearances from uniform increased echogenicity through to lesions containing large echo-free areas. Bilateral uniformly increased echogenicity has a poor outlook but in all other situations outcome cannot be accurately predicted from an early second trimester scan. Follow-up through pregnancy often allows a fairly accurate prognosis to be made but the appearance of the lesion does not accurately predict histology. A conservative approach to the antenatal management of unilateral lesions is recommended with long-term postnatal follow-up for all lesions because of the unknown long-term outcome for the lesions, many of which are symptomatic postnatally.