We provide evidence that the capacity of young children to engage in social interaction exceeds that suggested by Piaget in 1926. Rather than being collective monologues, the conversations between the subjects of this study (twin boys) were dialogues: the children attended to one another's utterances and provided relevant responses. This was observed for conversations which were referentially based as well as for sound play exchanges. This is not to say that the children experienced no difficulty in sustaining cooperative discourse. It could take a speaker several turns to secure the attention of the co-conversationalist and establish a discourse topic.