The International Classification of Diseases-11th revision (ICD-11) classification of personality disorders is the official diagnostic system that is used all over the world, and it has recently been renewed. However, as yet very few data are available on its performance. This study examines the Personality Inventory for ICD-11 (PiCD), which assesses the personality domains of the system, and the Standardized Assessment of Severity of Personality Disorder (SASPD), which determines severity. The Spanish versions of the questionnaires were administered to a community ( = 2,522) and a clinical sample ( = 797). Internal consistency was adequate in the PiCD (α = .75 to .84) but less so in the SASPD (α = .64 and .73). Factor analyses suggested a unidimensional or bidimensional structure for severity, while revealing that the personality trait qualifiers are organized into four factors: negative affectivity, detachment, dissociality, and a bipolar domain of disinhibition-anankastia. The mutual relationships between traits and severity were analyzed, as well as the ability of the whole system to identify clinical subjects. Although further improvements are required, the results generally support the use of the PiCD and the SASPD and help substantiate the new ICD-11 taxonomy that underlies them.