This longitudinal study analyzed data collected by the Preschool Curriculum Evaluation Research (PCER) project to examine home and preschool predictors of emergent literacy development. Through multiple regression analyses, the study evaluated those aspects of the home and preschool environment most strongly associated with the development of key preliteracy skills during preschool and kindergarten. Through the use of structural equation modeling, the study then tested and compared three potential models of emergent literacy. The 2,371 children included in the study (50.9% male; mean age = 4.6 years, SD = .32) attended 208 preschool programs across urban, rural, and suburban locations. Shared reading, literacy materials, learning activities, and enrichment activities in the home were assessed through a parent interview during the Fall of the preschool year. The quality and quantity of preschool instructional activities related to phonological awareness, print and letter knowledge, oral language, and writing, as well as classroom book reading were assessed during the Spring of the preschool year through the use of the Teacher Behavior Rating Scale (Landry, Crawford, Gunnewig, & Swank, 2002). Emergent literacy skills assessed during the Spring of the preschool and kindergarten years were based on standardized measures of phonological awareness, alphabet knowledge, writing, grammar, and vocabulary. Household income, gender, and ethnicity were controlled. Findings overall are modest. Shared reading and enrichment activities in the home, and preschool instructional activities focused on oral language, writing, and letter knowledge were found to be most significantly associated with pre-literacy skill development. Results suggest socioeconomic status is related to the development of oral language skills (β = .50, p < .01) independent of the home literacy environment. Structural equation modeling results validate the distinction between code- and oral language-based skills proposed by Storch and Whitehurst (2001), and demonstrate home and preschool literacy environments to be most strongly predictive of the development of oral language skills. Findings also reveal oral language skills to be strongly associated with the development of code-based skills in preschool, thereby mediating the influence of home and preschool contexts on the development of code-based skills (β = .79, p < .00).