Infants learn from adults readily and cooperate with them spontaneously, but how do they select culturally appropriate teachers and collaborators? Building on evidence that children demonstrate social preferences for speakers of their native language, Experiment 1 presented 10-month-old infants with videotaped events in which a native and a foreign speaker introduced two different toys. When given a chance to choose between real exemplars of the objects, infants preferentially chose the toy modeled by the native speaker. In Experiment 2, 2.5-year-old children were presented with the same videotaped native and foreign speakers and played a game in which they could offer an object to one of two individuals. Children reliably gave to the native speaker. Together, the results suggest that infants and young children are selective social learners and cooperators and that language provides one basis for this selectivity. (Contains 1 figure and 1 footnote.)