Craniofacial surgery in craniofacial dysostosis on airway obstruction was studied retrospectively in a consecutive series of patients. The records of 76 patients were reviewed, 27 with Apert syndrome, 47 with Crouzon's syndrome, and two with Pfieffer's syndrome. Of 172 operations, 148 were done for cosmetic reasons, hydrocephalus, or papillary oedema, and 24 were done for airway distress. Forty patients (23%) were children less than 13 years of age, and 22 underwent midface advancement procedures. Only 13 of these operations had been done for airway distress. Two were cured by operation and seven improved. After operation had failed to relieve the airway obstruction, a nasal continuous positive airway pressure device (nCPAP) was fitted to seven patients. The nCPAP relieved or improved airway obstruction recorded by a sleep study. As midface advancement in childhood rarely results in lasting improvement in breathing or aesthetics, it may well be advisable to postpone operation until the early teens. We conclude that with nCPAP operation can in most cases be deferred until a time when a permanent result can be achieved.