Objective: This study examined the effectiveness of traumatic incident reduction (TIR) among a sample of adults with trauma histories through a review of client records. TIR is a brief, structured, person-centered, memory-based intervention that helps individuals process traumatic memories, thus eliminating or significantly reducing negative psychological consequences and promoting insight and growth. Method: On average, participants (N = 247) were 37 years old (SD = 10.98), mostly women, and racially and ethnically diverse. Self-reported posttraumatic stress, anxiety, depression, and expectations for future success were assessed prior to treatment, midway, and after treatment. A series of analysis of covariance models with repeated measures were examined, controlling for participants' biological sex and total number of hours spent in psychoeducational groups. Results: Posttraumatic stress, anxiety, and depression symptoms were significantly reduced, and expectations for future success increased. Conclusions: Findings support the potential of TIR to positively impact clients' mental health and well-being.