Abstract: Objective: There is limited research examining factors associated with Dialectical Behavior Therapy (DBT) treatment retention among veterans, who are of critical interest given higher rates of suicide and borderline personality disorder (BPD). This study examined factors related to DBT treatment retention and BPD symptom trajectories among veterans. Methods: Participants were veterans enrolled in a comprehensive DBT program. 145 veterans presented to the program, and 115 veterans were deemed eligible and enrolled. The relationships between mental health care utilization, suicide-related factors, military-related trauma, and demographic variables with treatment retention and BPD symptom trajectories were examined. Results: Older adults were more likely to complete at least a portion of treatment, and veterans with higher education were more likely to complete treatment. Regarding treatment outcomes, a past year suicide attempt was associated with heightened baseline BPD symptoms and sharper reductions in BPD symptoms. Having a recent emergency room visit was associated with sharper reductions in BPD symptoms. Conclusions: These results begin the work of identifying factors associated with treatment retention and outcomes in this high-risk population—with the aim of informing research focused on understanding who is the most likely to benefit from DBT, as well as identifying potential factors to inform DBT program processes.