IMPORTANCE Borderline personality disorder (BPD) has been identified as a strong risk factor for suicidal behavior, including suicide attempts. Delineating specific features that increase risk could inform interventions.OBJECTIVE To examine factors associated with prospectively observed suicide attempts among participants in the Collaborative Longitudinal Study of Personality Disorders (CLPS), over 10 years of follow-up, with a focus on BPD and BPD criteria. DESIGN, SETTING, AND PARTICIPANTSThe CLPS is a multisite, naturalistic, prospective study of adult participants with 4 personality disorders (PDs) and a comparison group of adults with major depressive disorder and minimal PD features. Participants were all treatment-seeking and recruited from inpatient, partial, and outpatient treatment settings across New York,