Information about the adenoid mass is reviewed, and the phenomenon of gradual development of hypernasality as a result of adenoidal involution is described in two patients selected from a sample of 122 with repaired cleft palate. Three types of radiographically determined closure patterns of the velum against the adenoid pad are presented. Our clinical experience suggests that the results of aerodynamic studies, completed on a longitudinal basis, may identify patients who are at risk in maintaining normal resonance balance one year or more in advance of perceptual or radiographic evidence of velopharyngeal incompetency.