Borderline personality disorder (BPD) is a debilitating mental illness that affects approximately 1-2% of the general population. Researchers have increasingly come to view emotion dysregulation as a core feature of BPD. The present study examines the relationship between BPD symptomatology and emotion dysregulation using the Difficulties in Emotion Regulation Scale (DERS) in two college samples. BPD symptoms were assessed by self-report (MSI-BPD) in sample 1 and by semi-structured interview (SIDP-IV) in sample 2. Results suggest that emotion dysregulation accounts for unique variance in BPD even after controlling for traditional indicators of negative emotionality, including depression, anxiety, and negative affect. Findings support theories regarding the role of emotion dysregulation in BPD and provide directions for future research.