Interpersonal reality monitoring (IRM) refers to our ability to evaluate whether other people's memories reflect real or imagined events. The current work examined IRM and whether or not it can be affected by training and feedback. We found that people are better than chance and that the ability to accurately make this judgement can be improved or reduced with appropriate and inappropriate training, respectively. Understanding IRM has implications for applied psychologists interested in how people evaluate others' descriptions of past events (e.g., eyewitness testimony).