A substantial group of adolescents demonstrate behavioural patterns consistent with the DSM-IV-TR diagnosis of borderline personality disorder (BPD). In light of the paucity of empirically validated interventions for adolescents with BPD, there is a fundamental need to develop and assess novel treatments for this underserved population. Following the research evidence for the effectiveness of standard Dialectical Behavior Therapy (DBT) for adult outpatients as well as the growing evidence for the usefulness of modified DBT programs adapted for adolescents, the primary purpose of this study was to investigate the effect of a 12-week outpatient DBT skills group that included family members and that was provided as an adjunct to non-DBT individual therapy (i.e., Treatment As Usual) for multidiagnostic suicidal adolescent outpatients. This study also offered an opportunity to examine how DBT skills group intervention might be provided in a "real-world" community-based system of care. A natural consequence of conducting this type of research is having less rigorous control over facets of the investigation. In this study,process challenges impacted the research design, and, ultimately, the opportunity to reach valid conclusions about the effects of the DBT intervention on the basis of a pre-post research design and analysis. Preliminary results suggest that a DBT skills group intervention may be a useful intervention for adolescents but additional studies are required to validate the effectiveness of DBT with this population. Implications for treatment development, service delivery, and future research directions are discussed in light of the findings.