Personality disorders are defined in the current psychiatric diagnostic system as pervasive, inflexible, and stable patterns of thinking, feeling, behaving, and interacting with others. Questions regarding the validity and reliability of the current personality disorder diagnoses prompted a reconceptualization of personality pathology in the most recent edition of the psychiatric diagnostic manual, in an appendix of emerging models for future study. To evaluate the construct and discriminant validity of the current personality disorder diagnoses, we conducted a quantitative synthesis of the existing empirical research on associations between personality disorders and interpersonal functioning, defined using the interpersonal circumplex model (comprising orthogonal dimensions of agency and communion), as well as functioning in specific relationship domains (parent–child, family, peer, romantic). A comprehensive literature search yielded 127 published and unpublished studies, comprising 2,579 effect sizes. Average effect sizes from 120 separate meta-analyses, corrected for sampling error and measurement unreliability, and aggregated using a random-effects model, indicated that each personality disorder showed a distinct profile of interpersonal style consistent with its characteristic pattern of symptomatic dysfunction; specific relationship domains affected and strength of associations varied for each personality disorder. Overall, results support the construct and discriminant validity of the personality disorders in the current diagnostic manual, as well as the proposed conceptualization that disturbances in self and interpersonal functioning constitute the core of personality pathology. Importantly, however, contradicting both the current and proposed conceptualizations, there was not evidence for pervasive dysfunction across interpersonal situations and relationships.