This program of research will provide a better understanding of the early phonological development of children with cleft palate. Some children with cleft palate develop unusual speech patterns that have been labeled "compensatory" because they appear to be produced in response to an inability to achieve velopharyngeal closure and "maladaptive" because they are difficult to change once they have been established. Additionally, these patterns interfere with intelligibility and with the assessment of velopharyngeal function. Other children with similar structural problems do not develop these patterns. The studies proposed here will identify the factors associated with the development of undesirable articulation patterns and will describe the normal course of phonological development in children with cleft palate. This set of studies will follow a group of children with cleft palate and a matched group of normal children from the time they are 9 months old until they are 24 months old in an attempt to determine the origin and course of development of both adequate, appropriate phonological skills and compensatory patterns of articulation. All children will be seen once every three months. Additional speech samples will be obtained during the time children are learning to produce their first 50 words (all children). Acoustic analyses of the early vocalizations will be used to identify "speech-like" productions and both "speech-like" productions and meaningful words will be transcribed using standard IPA augmented by symbols designed for use with the speech of individuals with cleft palate. Within the cleft palate group, the relationship between the development of maladaptive compensatory articulation patterns (MCAP) in early speech and a number of factors will be examined. These factors include 1) hearing, 2) velopharyngeal competence, 3) the timing of primary palatal surgery relative to the onset of speech, and 4) the prelinguistic use of MCAP. The speech of children with cleft palate will be compared to the speech of non-cleft children to identify differences in the rate of acquisition of speech production milestones and differences in the frequency with which various phonemes and phoneme classes are targeted and produced by children with and without cleft palate.