The past quarter century of research on the development of speech perception has documented a number of important capacities that infants possess for recovering information from the speech signal. Such capacities provide the infant with the means to initially categorize speech input. Yet, because individual languages differ greatly in their sound structures, any language-general capacities for processing speech must eventually give way to ones that are more appropriately tailored to the specific language spoken in the infant's native environment. Recent studies suggest that during the second half of their first year, infants are learning about the specific properties and organization of native language sound patterns. Moreover, there is evidence that infants begin to adapt and adjust their capacities to the structure of their language input. In addition to outlining some of the landmarks observed in the development of speech perception capacities during the first year, some consideration will be given to how these capacities interact with the input to facilitate the acquisition of a native language.