The preliminary analysis indicated that the Defendant and Offender Screening Tool (DOST) provided a reliable and valid screening tool for the forensically relevant assessment of psychopathology among inmate populations. In particular, all subscales demonstrated acceptable internal consistencies and test-retest reliabilities and they demonstrated the ability to discriminate between target and comparison groups. The findings thus provide preliminary support for the use of the DOST in forensic and correctional settings. Development of the DOST involved the drafting of initial items for five identified subscales. Items were examined for content and adherence to underlying theoretical constructs by an independent body of reviewers. Subscales were then evaluated for individual utility through administration to an inmate population as well as college students. Following revisions, the complete DOST was administered to 381 inmates. Data analysis involved the use of a principal components factor analysis. The authors conclude that the DOST performed satisfactorily in its initial evaluation. Future research should continue to examine the validity and usefulness of the DOST in multiple correctional settings. Tables, appendix, references