ABSTRACT:Selected behavioral features felt historically and empirically to be significant in the borderline personality disorder were evaluated in 4,800 psychiatric inpatients. Variables measured included number of hospitalizations and type of discharge, suicidal behavior, physical violence, and outcome after discharge. A statistical analysis was performed to determine the relationship between depth and severity of borderline traits and the aforementioned behavioral features. Results indicated that irregular discharges, frequent suicide attempts, first suicide attempt prior to age 40, violence within and outside the hospital, and gradual deterioration in social and occupational functioning were found significantly more often in patients with high levels of borderline personality traits.