Different writing systems in the world select different units of spoken language for mapping. Chinese, usually considered a logographic writing system, maps a printed character to a corresponding monosyllabic morpheme. This proposed study will investigate biliteracy development of native Chinese (L1) children compared to native Korean children in learning to read English as a second language (L2). The Korean alphabet, Hangul, maps letters onto phonemes just as English, Russian, and Italian do. Recent research on literacy development of children learning to read English from another alphabetic system such as Spanish has started to provide consistent results on the strong facilitation between L1 and L2 reading skills. However, to date few comparable studies have been carried out on biliteracy development of children learning to read English from an orthographically or typologically different writing system such as Chinese. This longitudinal study will follow about 200 children from kindergarten to grade 2 (about 100 in each language group). We will test children once every year. Parallel experiments and tests in L1 and L2 will be designed to examine the three major word reading components - phonological, orthographic and meaning processing. Word identification skills in L1 and L2 will be tested. With data from these measures across time, we plan to investigate cognitive consequences of alphabetic (Korean) versus nonalphabetic L1 (Chinese) literacy experiences for learning to read English L2 at different time points; to examine the concurrent and predictive relationships between various basic reading components and word identification skill within three different languages (Chinese, Korean and English); to explore the concurrent and predictive relationships between the reading components and word identification skill across languages (Chinese-English vs. Korean- English). These findings will provide insight into the interaction between universal and language-specific processes of biliteracy development.