Most research on dual language learners (DLLs) in preschool has focused on language and literacy development. Less work has been done on their play and social interactions, in spite of the importance of these for development and learning. Although DLLs possess many social strengths, they also face challenges, particularly in an English-dominant classroom. In the present investigation we examined the influence of three factors on DLLs play interactions with peers in preschool: teacher support, peer interactions, and play materials. We recorded the free play of 12 DLLs who were of low English proficiency in English-dominant classrooms and coded aspects of these three factors. Using multiple regression analysis we identified four variables that predicted the frequency of DLLs’ interactions with their peers. Teacher interactions in play that included a child’s home language—though not overall teacher contact, alone—verbal and positive play behaviors by peers, and the availability of blocks and replica play toys. Implications of our findings for classroom practice are offered. (author abstract)