The establishment of a safe and efficient method of feeding in infants with cleft lip and palate is one of the major concerns for parents and the cleft lip and palate team. In spite of a poor knowledge base of the physiological basis of feeding difficulties amongst these infants, numerous management techniques are advocated. Few however are scientifically evaluated. ITie use of pre-surgical orthopaedics (PSO) is one such technique. This thesis reports a randomised control trial investigating the effect of PSO on feeding in infants with unilateral cleft lip and palate (UCLP) or isolated cleft palate (ICP). Infants with non-syndromic UCLP or ICP were eligible for inclusion in the trial. Following recruitment they were randomised to PSO or No PSO. All other aspects of management were standardised. Primary outcome measures were oral motor assessment and anthropometry at 12 months of age. Secondary outcome measures included parent report of feeding at 3, 6 and 12 months of age, physiological measures of feeding, oral motor assessment and anthropometry at 3 and 6 months of age. Thirty-four infants with UCLP and sixteen infants with ICP were recruited. Equal numbers within each cleft type were randomised to PSO and No PSO. Although this trial was underpowered the results suggest that PSO have no significant effect on feeding or general body growth post palate repair at 12 months of age. While occasional improvements were found to be associated with the use of PSO pre palate repair at 6 months of age, the differences were not considered clinically significant.