Recently we saw 9 infants with life-threatening respiratory distress. Four patients had bronchogenic cyst, 2 had cystic adenomatoid malformation, and 9 had congenital labor emphysema. Another group of 14 older children had recurrent infection and hemodynamic abnormalities, which responded to operative intervention. Each child required an appropriate resection following definitive diagnosis. These lesions represent a spectrum of closely related anomalies that arise during an early stage of embryonic lung bud maturation. Bronchoscopy is rarely useful, but special roentgenographic studies, including perfusion scans and arteriography, are usually diagnostic. Our operative experience is used to emphasize the urgency of precise diagnosis and surgical management of this poorly recognized clinical syndrome. © 1979, The Society of Thoracic Surgeons. All rights reserved.