Interpersonal dysfunction and aggression are features that are frequently found in individuals with borderline personality disorder (BPD); however, few studies have examined the possible causal relationship between aggressive actions and interpersonal problems. In a nonclinical sample of 98 women with a range of BPD features, the present study examined the prospective relationship between aggressive behaviors and negative interpersonal events using a weekly diary method. Results showed that higher BPD symptoms were related to higher aggression and more negative interpersonal events. Furthermore, the aggressive acts endorsed among women with more BPD features were more likely the effect, rather than the cause, of the negative interpersonal events they experienced. Implications for interventions targeting aggression among women with elevated BPD features and suggestions for future research are discussed.