An article by Angeline S. Lillard and others published in the January 2013 issue of Psychological Bulletin about the impact of pretend play on child development raised a number of issues about play studies and child psychology. They claimed that, contrary to current theories on the subject, the evidence of many studies does not support causal explanations of play's relationship to most childhood development. In this article, authors Kasari, Chang, and Patterson review these arguments about play and devlopment in relation to children with autism-children who show specific deficits in pretend play. They argue that the study of these children provides a unique opportunity to consider which elements in play are important and how play skills are associated with different periods of child development. They conclude that, because pretend play requires intervention for the majority of children with autism, improving pretense in these children may shed more light on the causal impact of pretense on later developing skills in children. Key words: child development and pretend play; children with autism; funtional play; intervention in play; symbol play.