The present study investigated personality change over the course of a four-year longitudinal study in N = 452 older adults who responded to the 9/11 attacks on the World Trade Center ( Mage = 55 years, SD = 0.41). This sample provides the rare opportunity to compare normative findings of personality change with change in a unique group with a common trauma. Participants completed the Faceted Inventory of the Five-Factor Model and the Big Five Inventory-2 across four years. Latent growth modeling showed significant mean-level decreases in Openness and Extraversion. At the facet-level, significant decreases were found for Aesthetic Sensitivity, Creative Imagination, Intellectual Curiosity, Anxiety, Anger Proneness, Positive Temperament, Venturesomeness, Ascendence, Empathy, and Achievement Striving. Further, responders showed variability in change—in particular, for Neuroticism and its facets. Regressions from exposure level and age on personality change were also examined. Results highlight the importance of facet-level analysis, as significant change was found only for certain facets within domains—sometimes when the domains showed no change. Differences between responders and normative comparisons were examined. Responders share unique trauma and personality findings may allow clinically useful information on the mental-health problems that responders experience.