Many Spanish-speaking children with limited English proficiency have difficulty learning to read in English and are at risk for emotional and behavioral problems due to school failure. At the same time little is known about how the two languages interact and relate to reading acquisition. The main purposes of the proposed longitudinal research are to better understand (1) how Spanish-speaking children become proficient in English and (2) how they learn to read and become literate in English. In this regard, we intend to expand the knowledge base on language transfer by studying how the phonological, lexical, syntactical, and morphological proficiencies in Spanish and English are related among and between the two languages and how they relate to reading acquisition in both languages. Also, to provide a more thorough understanding of the determinants and contexts that influence development, we propose to describe and study both qualitatively and quantitatively (a) the influences of socio-economic status (SES), selected family and child characteristics, and family experiences (e.g. literacy practices), and (b) children's educational experiences (exposure to different reading and language programs), parent involvement in school activities and parent school personnel relationships. Finally, we will have an opportunity to contribute to the existing knowledge base on models for assessing risk for developing reading difficulties in Spanish-speaking children by using different combinations of Spanish language measures. To accomplish these goals we propose to sample 100 kindergarten children who represent all levels of English proficiency and follow them though the 3rd grade, and to draw a random sub-sample of 100 parents who represent all SES levels to study more extensively than the initial 600 parents. This approach is designed to study the maximum variance in individual differences in child growth and a rich qualitative portrait of families and schools. ? ?