AbstractOver the last decade, a healthy shift in the trauma literature has meant that published theory and research in the posttraumatic growth (PTG) domain has burgeoned, but the validity of the self‐report questionnaires used to measure PTG has recently been criticized. Corroboration of these subjective reports by an observer would provide convergent validity. Therefore, this study's aim was to validate the Posttraumatic Growth Inventory (PTGI; Tedeschi & Calhoun, 1996). Sixty‐one trauma survivors and 61 paired significant others completed the PTGI. A significant correlation was reported between the total PTGI scores of the trauma survivors and the corroborating significant others, supporting the use of the PTGI as an appropriate measure of positive posttrauma changes.