Fifty patients with clefts (30 unilateral cleft lip and palate (UCLP), 9 bilateral cleft lip and palate (BCLP), and 11 cleft palate only (CP), mean age 25 years) treated with Le Fort I osteotomy were compared retrospectively from cephalograms taken shortly before operation, and at six months and one year postoperatively. Patients with bimaxillary surgery or previous velopharyngoplasty, or both, were excluded. Maxillary advancement was moderate in all groups. One year postoperatively there was a significant change (73%-90% of the surgical advancement) in the sagittal depth of the nasopharyngeal airway but not in the depth of the oropharyngeal airway, the length of the soft palate or the position of the hyoid bone. The nasopharyngeal airway was largest in the CP group both preoperatively and postoperatively. Eleven patients (7 CP, 4 UCLP) had a velopharyngoplasty after the osteotomy to improve their speech. There was no difference in the nasopharyngeal airway in the patients treated by velopharyngoplasty compared with those not so treated, but they seemed to have the shortest maxillas and the greatest surgical changes vertically.