2006 - Friday May, 19th, 2:30 - 4:30 pm Ecole Normale Supérieure, 45, rue d'Ulm, Paris The ontogenetic emergence of co-operative communication Infants begin expressing their communicative intentions also at around the first birthday. In addition to co-operative requests (expressions of desire that helpful others are supposed to respond to helpfully), infants also communicate prelinguistically for two other basic motives : (1) to help others by providing them with needed information (informing) ; and (2) to simply share interest and attention with others to outside events and activities declaratively. They also, on occasion, gesture for others iconically [deictic gestures being triadic analogues of ape attention-getters and iconic gestures being triadic analogues of ape intention movements]. A series of experiments suggests that these early communicative acts involve full-blown shared intentionality, including participation in joint attentional (intersubjective) frames with distinct perspectives, participation in joint activities with shared goals and intentions, and the comprehension of co-operative communicative intentions. Less certain is how infants acquire these skills (imitation ? ritualization ?), and whether infants' comprehension of communicative intentions is fully Gricean (she intends that I know that she intends that we share attention to X). Studies of how infants acquire their earliest skills of linguistic communication in discourse help to resolve some of these outstanding issues.