Executive functions (EF) are known to be a multidimensional construct in adults; however, the underlying dimensions of EF in early childhood are unclear. Theoretical models of EF have generally suggested the importance of language, attention, and inhibition abilities as developmental foundations for EF abilities. This study investigated the construct validity of EF by administering a diverse battery of measures of EF along with cognitive measures representing different theoretical models of EF (language, attention, and inhibition) to 70 preschool children. The EF battery included measures of working memory (verbal and nonverbal), set shifting, and problem solving. A maximum likelihood factor analysis with oblimin rotation resulted in a three factor model; however, only two factors (language and inhibition) were related to EF measures. Results from the current study suggest language and behavioral inhibition are two foundational latent abilities for the development of EF abilities in early childhood. Attention, although important in many EF theories, may also be important for cognitive development but appears to be less important for EF abilities in preschool children. Results from this study suggest executive functions in early childhood consist of multiple distinct but interrelated components that are associated with underlying cognitive foundations.