Three experiments investigated the effect of an adult's social cues on 2- and 3-year-old children's ability to use a sign or symbol to locate a hidden object. Results showed that an adult's positive, engaging facial expression facilitated children's ability to identify the correct referent, particularly for 3-year-olds. A neutral facial expression and the presence of the adult's hand also facilitated performance, but to a lesser degree than did an engaging facial expression. The effect of the adult's social cues was greater for relatively unfamiliar signs and symbols (replica or arrow) than it was for a more familiar sign (pointing finger). These findings indicate that non-directional social cues such as facial expression help to convey communicative intent and facilitate children's comprehension of signs and symbols.