Theory and empirical work suggest inclusion preschool improves the school readiness of young children with special needs, but only 2 studies of the model have used rigorous designs that could identify causality. The present study examined the impacts of the Boston Public prekindergarten program—which combined proven language, literacy, and mathematics curricula with coaching—on the language, literacy, mathematics, executive function, and emotional skills of young children with special needs (N = 242). Children with special needs benefitted from the program in all examined domains. Effects were on par with or surpassed those of their typically developing peers. Results are discussed in the context of their relevance for policy, practice, and theory.