Research has shown so far the efficacy of day hospital treatment programs for patients with a personality disorder experiencing a crisis episode. However, relatively few studies have relied on a dimensional definition of personality pathology, despite the rise of dimensional models of personality disorders in recent years. The objective of this study is therefore to delimit profiles of patients with a personality disorder admitted in a day hospital treatment program using dimensional models of personality and attachment, and psychological distress. A total of 287 patients with a personality disorder completed a series of self-report measures assessing the Big Five personality traits, the Dark Triad components, insecure attachment dimensions, and psychological distress. Cluster analysis, successively using hierarchical and TwoStep algorithms, yielded a three-cluster solution. The three clusters were labeled: Externalizing-Antagonistic, Internalizing-Detached, and Relational and Emotional Difficulties. Each cluster showed a specific pattern of scores on Big Five personality traits, Dark Triad components, and insecure attachment dimensions, and all clusters were associated with clinically significant levels of psychological distress. Results highlight that features from the externalizing, internalizing, and/or detachment spectra of psychopathology distinguish clusters of PD patients admitted in a day hospital treatment program. These clusters are aligned with descriptions found in the recently proposed Hierarchical Taxonomy of Psychopathology. A continuum of severity in personality impairments across the three clusters was also discovered. The clinical and conceptual implications of the three-cluster solution are discussed.