Abstract
This article outlines a model of personality disorder (PD) diagnosis that combines clinically useful constructs from the Diagnostic and Statistical Manual of Mental Disorders (DSM) with assessment procedures that maximize reliability and clinical utility while minimizing problems associated with threshold-based PD classification. I begin by addressing limitations in the current DSM conceptualization of PDs: excessive comorbidity, use of arbitrary cutoffs to distinguish normal from pathological functioning, failure to capture variations in the adaptive value of PD symptoms, and inattention to situational influences that shape PD-related behaviors. The revisions proposed by the DSM-5 Personality and Personality Disorders Work Group help resolve some of these issues, but create new problems in other areas. A better solution would be to employ a multidimensional model of PD diagnosis in which clinicians (a) assign a single dimensional rating of overall level of personality dysfunction, (b) provide separate intensity and impairment ratings for each PD dimension, and (c) list those personality traits-including PD-related traits-that enhance adaptation and functioning. Preliminary evidence bearing on the multidimensional model is reviewed, and broader clinical and empirical implications of the model are discussed.