Between 1948 and 1980, 107 of 164 patients survived after repair of a congenital diaphragmatic defect. Sixty of the survivors (mean age, 29.6 years; SD, 9.0 years) underwent clinical examination, chest radiography, spirometry, and diffusing capacity measurement 11 to 41 years after the diaphragmatic repair. Twenty-seven of the 60 had body plethysmography, xenon 133 radiospirometry, and a test of bronchial hyperreactivity. Subjective physical performance was below average for eight patients (13%), seven patients (12%) had asthma, and four patients (7%) reported increased susceptibility to respiratory infections. Thirty-one patients (52%) had ventilatory impairment, which was obstructive in nine (15%), restrictive in seven (12%), and obstructive and restrictive in 15 patients (25%). Nine (35%) of the 26 patients tested had bronchial hyperreactivity. The presence of ventilatory impairment and bronchial hyperreactivity correlated with the initial clinical severity of the affliction. Chest asymmetry (29 patients; 48%) and scoliosis (16 patients; 27%) were more common among patients with ventilatory impairment than among those with normal spirometric findings. Ventilatory impairment and thoracic deformities are common in adults with repaired diaphragmatic defects. Surveillance should begin in infancy and continue into adulthood.