Results indicated that the overall profile of the SMU sample closely resembled that of traditional inpatient psychiatric samples. BPRS scores from the SMU sample revealed that 22 percent of the SMU residents had total scores greater than 24, suggesting the presence of severe psychosocial distress. The BPRS was found to have satisfactory reliability, effectiveness, and construct validity, indicating that the BPRS does indeed measure psychosocial impairment. A significant number of participants met the criteria for serious mental illness. A comparison of SMU subscales scores with scores obtained from other studies offered enough differences and similarities to call for further study. The findings suggest that the BPRS can offer a flexible and reliable framework that escapes the interpretative or analytic rigidity of a diagnostic instrument. Participants were a voluntary sample of 87 male SMU residents who were housed in 3 of Washington State’s SMUs and who completed the Brief Psychiatric Rating Scale (BPRS), which measures 18 of the most common psychiatric symptoms. The BPRS was administered via semi-structured interviews. Data were also drawn from inmate records, unit records, and the narrative notes of frontline staff. Data analysis was performed using SPSS software and included the use of factor analysis. Future research should focus on the development of a model that incorporates the BPRS with other psychiatric measures that are designed to situate individual factors within the context of an extreme environment, such as an SMU. Tables, notes, references