Background: Detecting patients with borderline personality disorder (BPD) is important, and feasible screening instruments are needed. Aims: To investigate our Finnish translation of the McLean Screening Instrument for Borderline Personality Disorder (MSI-BPD) as a screen for BPD among psychiatric outpatients, its psychometric and screening properties, and feasibility in improving the recognition of BPD. Methods: We screened 302 consecutive psychiatric outpatients at the Department of Psychiatry at the Helsinki University Central Hospital in Finland for BPD using the Finnish MSI-BPD. Of the patients, 69 (23%) were assigned to a random sample that was stratified according to the number of screens returned to the outpatient clinics, and further stratified into the three strata, high scores deliberately enriched, according to the MSI-BPD scores. Finally, a stratified random sample of 45 patients was interviewed with the Structured Clinical Interview for DSM-IV Axis II Personality Disorders (SCID-II) by the interviewers blind to the patients' MSI-BPD scores. Results: One third (29%) of 302 screened patients had a positive MSI-BPD. The internal consistency of the MSI-BPD was good (Cronbach's alpha = 0.77). Of the 45 patients interviewed with the SCID-II, 11 (24%) were found to have BPD, five (46%) of whom a previously clinical diagnosis. In a ROC analysis, the optimal cut-off score was 7. Conclusions: The translated MSI-BPD was found to be a feasible screen for BPD in Finnish psychiatric outpatient care. Further studies investigating the clinical utility of MSI-BPD in larger clinical samples are warranted.