Fifty Veterans who are currently receiving treatment in the PTSD RRTP at a Midwest VA will be recruited to participate in a Group PE protocol. Participants will engage in 12, 90-minute sessions of Group PE over the course of 6 weeks. Treatment consists of psychoeducation, rationale for treatment, and in vivo exposure to reduce trauma-related avoidance and thereby improve PTSD symptoms. PTSD symptoms will be measured via the PCL-5. The goal of this pilot study will be to determine whether or not it will be feasible to conduct a full-scale trial of Group PE in the current setting by testing the process, resources, management, and scientific basis of the planned trial. As such, the proposed study will primarily assess feasibility outcomes and not efficacy outcomes. The investigators will assess number of participants screened, number meeting inclusion criteria, adherence of participants to the proposed treatment (measured via number of sessions attended), standard deviation of the outcome measure (PCL-5), response rates to questionnaires, and loss to follow-up. The investigators will also measure clinicians' adherence to protocol and acceptability of the treatment to patients.