- This article examines the cognitive underpinnings of spontaneous and prompted pretend play in 28 young children with autism, 24 children with other developmental disorders, and 26 typical children. The article compares theories that consider either theory of mind (ToM) or executive function (EF) to be causally important deficits in the development of pretend play in autism and important factors in pretend play. Each of these two theories posits a cognitive precursor to pretense, which would need to be present in typical development, and the absence of which could explain pretend play deficits in children with developmental disabilities such as autism. We tested which of these theories better predicts a child's production of pretend play. Children with autism were significantly delayed on pretend play scores. They also had significant deficits in our ToM measure, but not our EF measures. Regression analyses suggested a role for our measure of generativity, one of the EF measures.