The past 20 years have seen research on language acquisition in the cognitive sciences grow immensely. The current paper offers a fairly extensive review of this literature, arguing that new cognitive theories and empirical data are perfectly consistent with core predictions a behavior analytic approach makes about language development. The review focuses on important examples of productive linguistic behavior: word learning and early grammatical behavior. Language experience, through social and other contingencies, influences language development directly. Through these contingencies, the structure of language behavior exhibits a gradual emergence.