Imagery Rescripting (ImRs) is widely used in psychological treatment to help clients process aversive memories. However, protocols often vary. My thesis investigates a specific adaptation: extending the intervention to include a "positive ending" aimed at evoking positive affect. In this session, I will present our findings on how this modification influences the core therapeutic mechanisms of meaning change and mastery in a sub-clinical student sample. While results suggest a positive ending can further drive meaning change, mastery remained unaffected. A possible mediating role for mastery on meaning change was not established. An interpretation of these results and its implications for future research will be discussed.