An experimental outcome study with trauma-related symptoms was conducted to examine the effectiveness of traumatic incident reduction (TIR). It is a brief memory-based therapeutic intervention and was used to treat symptoms of posttraumatic stress disorder (PTSD), depression, anxiety, and low expectancy of success (i.e., low self-efficacy). A randomized pretest-postest control group design with 123 female inmates (mean age 32 yrs) in a federal prison, was used to evaluate the efficacy of the interventive procedure. Results showed significant differences between treatment and comparison control conditions on all measures at postest and 3-mo follow-up intervals except for the PTSD Intrusion subscale at the postest interval. The marked improvement of the treatment condition by comparison to those in the control condition supports the contention that TIR is an effective intervention with female inmates. The significant results on all measures at the follow-up time interval provide persuasive evidence of the stability of the interventive effects. The significance of this therapy model for use by practitioners with social work populations is highlighted. (PsycINFO Database Record (c) 2019 APA, all rights reserved)