Children often witness or are victims of crimes, and so can provide crucial details. Children are often believed to unreliable witnesses. Yet, a new body of research has challenged previous beliefs, by providing evidence that young children can assess their own memory accuracy, because they can know when their memories are accurate or not. In this study, we are recruiting children between the ages of 4 and 8 to examine which behaviours can tell us more about the accuracy of children’s memory monitoring.