When and how do children develop an understanding that memory can fail in two fundamentally different ways. One type of memory failure involves forgetting, or being unable to remember a particular piece of information despite one’s best efforts. The other type involves “misremembering,” or confidently remembering something incorrectly. We (Jaswal & Dodson, 2009) have observed that 6-year-olds understand that memory is fallible not just because it is subject to forgetting, but also because it is subject to distortion. By contrast, 5-year-olds have a more limited awareness of the causes of memory failures and primarily memory failure in terms of forgetting (i.e., guessing based on the absence of remembered information).