Anomalies of bronchial branching are infrequent and may be difficult to diagnose. The bridging bronchus is a rarely reported anomaly that may not be as sporadic as once thought. We describe an infant with respiratory distress whose right middle and lower lobes were supplied by a bridging bronchus arising from the left main bronchus. The airway anatomy was defined using flexible and rigid bronchoscopy and helical computed tomographic scanning, enabling successful surgical repair. We review current literature on the bridging bronchus as well as the possible embryological basis for this defect.