A primary function of facial displays is to communicate messages to others. Bavelas and Chovil (1990) proposed an Integrated Message Model of language in which nonverbal acts such as facial displays and gestures that occur in communicative (particularly face-to-face) interactions are viewed as symbolic messages that are used to convey meaning to others. One proposition of this model is that these nonverbal messages will be shaped by the social components of the situation. The present study attempted to delineate more precisely the components of sociality that explicitly affect the use of facial displays in social situations. Frequency of motor mimicry displays in response to hearing about a close-call experience was examined in four communicative situations. In one condition, participants listened to a tape-recording of an individual telling about a close-call event. In two interactive but nonvisual conditions, participants listened to another person over the telephone or in the same room but separated by a partition. In the fourth condition, participants listened to another person in a face-to-face interaction. The frequency of listeners' motor mimicry displays was found to vary monotonically with the sociality of the four conditions. Actual presence and visual availability of the story-teller potentiated listener displays. The results support the proposition that facial displays are mediated by the extent to which individuals can fully interact in communicative situations.