People with severe mental disorders have a high prevalence of physical and sexual abuse and rates of PTSD in this population are also extremely high. In addition to the hallmark PTSD symptoms of reexperiencing, avoidance, and hyperarousal, these individuals are at increased risk of other problems: mental health symptoms (depression, generalized anxiety, somatization), hostility, interpersonal difficulties, and revictimization. The Men's Trauma Recovery and Empowerment Model (M-TREM) is a preliminary adaptation for men of the women's TREM group treatment, which has been found to be effective in addressing PTSD and closely related consequences of interpersonal violence among women with severe mental disorders. The proposed project has two major aims: (1) to refine the preliminary M-TREM group intervention and to complete the leader's manual and accompanying materials, including a revised Fidelity Scale for assessing leader adherence to the treatment model; and (2) to examine the effectiveness of the MTREM group in a pilot study. In order to accomplish these aims, a research and clinical team from Community Connections in Washington, DC and the New Hampshire-Dartmouth Psychiatric Research Center will carry out the following tasks: (1) revise the existing manual; conduct two M-TREM groups; gather member, leader, and observer feedback; and refine the treatment manual accordingly; (2) enroll and randomly assign 60 men with PTSD and severe mental disorders to either a control condition of Services as Usual (SAU) or to M-TREM plus SAU (the latter condition will use the refined manual); (3) assess at baseline, post-treatment, and 3-month follow-up points the following outcomes: PTSD symptom severity, other mental health symptoms (depression, anxiety, and somatization), hostility, social relations, and revictimization; (4) examine within-group changes over time and conduct preliminary tests of the hypotheses that M-TREM will, in comparison to SAU, lead to decreased symptoms and enhanced social relations. ? ?