Borderline personality disorder (BPD) represents a highly prevalent, severe and difficult-to-treat mental health problem.

This paper considers methods, instruments and strategies for assessing BPD as described within the frame of the DSM-IV classification.

Following the general diagnostic approach introduced by Van Praag in biological psychiatry, a two-tier diagnostic strategy for the descriptive diagnostic assessment of BPD is recommended. Axis one results in a DSM-IV Axis II categorical diagnosis, whereas axis two refers to a symptomatological, dimensional or functional approach, in which the psychological dysfunctions of the nosological syndrome are depicted. Moreover, in a clinical context a basic aim of the diagnostic evaluation is to obtain therapeutically valid information that leads to a constructive conceptual framework, to a case formulation in which therapeutic interventions are understood, selected and implemented. This framework should be based on a biopsychosocial theoretical model and its application in the clinical context involves feedback to the patient, in which the descriptive evaluation is integrated with etiological; and pathogenic elements using an idiographic approach. This therapeutically orientated diagnostic strategy is illustrated by the use of the ADP-IV (Assessment of DSM-IV personality disorders) questionnaire within a cognitive behavioral orientation.