The long-term objective of this project is to determine the interaction between phonological development in bilingual children and the language of parents and the community (including the language of instruction in schools). The specific aim of this research project is to investigate the phonological skills in Spanish-English bilingual children with varying levels of output to test the hypotheses that: (1) there will be an interaction between direct measures of language skills, frequency of language output and phonological skills such that exposure and use variables will account for the variance on speech sound accuracy and (2) the relative phonological skills of bilingual children and monolingual children will vary according to frequency of output in each language. If these hypotheses are supported, they suggest that there is a threshold of output necessary for bilingual children to achieve commensurate phonological skills with monolingual children and that only certain exposure and use variables will predict speech sound accuracy. Participants, ranging in age from 4;0-5;11, will consist of 150 typically developing, Latino children: 50 Spanish-English bilingual children, 50 monolingual English-speaking children, and 50 monolingual Spanish-speaking children. Single word and connected speech samples in English, Spanish, or in both languages will be elicited. To measure the phonological skills of the children, one independent and six relational analyses will be completed. Statistical analyses include (1) Pearson correlations to determine the relationship between frequency of output and phonological skills, (2) a multiple regression to examine the extent to which exposure variables account for the variance on speech sound accuracy, and (3) a MANCOVA to examine the phonological skills of monolingual and bilingual children. Findings from this project will indicate (1) an increase in phonological skills as output in each language increases such that direct measures of language skill and percentage of output at home will significantly predict speech sound accuracy and (2) phonological skills will be significantly different for some, but not all, groups of bilingual and monolingual children, depending on frequency of output and exposure to each language. The proposed project also has clinical implications, suggesting the need to treat phonological disorders in bilingual children differentially, depending on frequency of output and other exposure and use variables. [unreadable] [unreadable] [unreadable]