This study compares the topography of the pharyngeal structures of 115 patients with isolated and combined cleft palates with the topography of the pharyngeal structures of 115 patients without cleft palates. The study revealed that the sagittal dimensions in the cleft palate patients are significantly reduced. The maximum closeness can be observed at the lower margin of the velum. In order to clarify growth dependent change of the sagittal pharynx dimensions the growth of the pharynx of 61 cleft palate patients was documented at 4 different points in time between age 7 and age 18. Over this period of growth only a slight increase in the sagittal plane of the pharyngeal area was observed. Especially conspicuous was the stagnation of the distance of the lower margin of the velum to the posterior pharyngeal wall. An increase in air passage resistance, which is the cause of incompetent breathing with all its consequences for growth and dentition development, is derived from these topographical relationships. The study concludes that the postoperative functional competence of the velum is a conditio sine qua non not only in relation to speech but also in relation healthy breathing.