This study examined the impact of training mothers to talk elaboratively about the past on children's understanding of mind. The researchers randomly assigned 102 mothers of 19-month-old children to a training or no-training group. Mothers in the experimental group received training in an elaborative style of talking about the past when children were 21, 25, and 29 months of age. Children were assessed on a battery of theory-of-mind tasks at 44 months. Results showed that children with initially lower levels of expressive vocabulary in the trained group benefited from elaborative talk about the past in terms of their understanding of mind. The article discusses the role of elaborative reminiscing, and specifically the importance of elaborative questions about the past, in children's growing representational skills.