Extreme and varied reactions are often encountered when working with patients with personality disorders. Similarly, patients with personality disorder may also hold polarised opinions of the staff involved in their treatment. This study explored the relationship between severity of personality disorder and interpersonal style in patients admitted for treatment to a secure psychiatric unit. Up to four nurses rated each patient's interpersonal style using the Impact Message Inventory, a self-report transactional inventory. Patients then rated the interpersonal style of these same staff. Contrary to expectations, severity of personality disorder was not associated with patients' interpersonal style or to variance in nurses' assessments of patients' interpersonal style. However, patients with more severe personality disorder tended to show greater variability in their assessment of nurses' interpersonal style, specifically their appraisal of staff members' interpersonal dominance. Implications for the assessment of offenders admitted for treatment of their personality disorder are discussed.