The categorical diagnosis of borderline personality disorder (BPD) is currently discussed as sufficiently reliable and valid. However, specific standardized instruments to measure the degree of the symptomatology are currently not available. Based on the criteria of DSM-IV, the Diagnostic Interview for Borderlines (DIB-R) and the opinion of clinical experts and borderline-patients, a self-rating scale was developed to quantify the intrapsychic strain of patients with BPD. 308 female borderline-patients scored the 99 items. Factor analyses revealed seven factors: self-image, affect regulation, autoaggression, dysthymia, social isolation, intrusions and hostility. Analyses of reliability and validity revealed promising results.