This study reports on the prevalence and correlates of clinician-diagnosed DSM-IV personality disorders (PDs) in a nationally representative sample of the US population. Using the International Personality Disorder Examination (IPDE), the researchers administered screening questions to a subsample of 5692 participants from the National Comorbidity Survey Replication (NCS-R). Multiple Imputation (MI) was used to estimate prevalence and correlates in the full sample. The results showed that the prevalence of any PD was 9.1%, with Cluster A (5.7%), Cluster B (1.5%), and Cluster C (6.0%) PDs being the most common. PDs were significantly comorbid with a wide range of Axis I disorders, and functional impairments associated with PDs were largely explained by Axis I comorbidity. The findings suggest that the main public health significance of PDs lies in their effects on Axis I disorders rather than their impact on functioning. The study also highlights the high comorbidity of PDs with Axis I disorders, raising questions about the arbitrary separation of PDs from Axis I disorders in the DSM nomenclature.This study reports on the prevalence and correlates of clinician-diagnosed DSM-IV personality disorders (PDs) in a nationally representative sample of the US population. Using the International Personality Disorder Examination (IPDE), the researchers administered screening questions to a subsample of 5692 participants from the National Comorbidity Survey Replication (NCS-R). Multiple Imputation (MI) was used to estimate prevalence and correlates in the full sample. The results showed that the prevalence of any PD was 9.1%, with Cluster A (5.7%), Cluster B (1.5%), and Cluster C (6.0%) PDs being the most common. PDs were significantly comorbid with a wide range of Axis I disorders, and functional impairments associated with PDs were largely explained by Axis I comorbidity. The findings suggest that the main public health significance of PDs lies in their effects on Axis I disorders rather than their impact on functioning. The study also highlights the high comorbidity of PDs with Axis I disorders, raising questions about the arbitrary separation of PDs from Axis I disorders in the DSM nomenclature.