The purpose of this pilot study was to explore differences in the level of personality functioning, symptom severity, and personality pathology in patients with mixed sensory-motor functional neurological disorder (conversion disorder). Individuals with psychogenic nonepileptic seizures were not included. We recruited 15 patients, mean age of 33.5 years (SD, 11.4 years), 13 females and 2 males, from an outpatient clinic for psychotherapeutic treatment. We assessed the patients using the Structured Clinical Interview for DSM-4 Axis II Personality Disorders, the SCL-90-R, the Karolinska Psychodynamic Profile, and the Defense Style Questionnaire. We were able to distinguish two levels of difficulty in relation to personality functioning as distinct subgroups: 1) "neurotic" with less severe or moderate personality psychopathology and 2) "borderline" with severe personality psychopathology. Furthermore, we concluded that all patients showed severe deficits in personality functioning. The study points out the clinical relevance of identifying personality functioning as part of an assessment in the preparation of a treatment strategy.