Despite substantial research use, measures of the five-factor model (FFM) are infrequently used in clinical settings due, in part, to issues related to administration time and a reluctance to use self-report instruments. The current study examines the reliability and validity of the Five-Factor Model Score Sheet (FFMSS), which is a 30-item clinician rating form designed to assess the five domains and 30 facets of one conceptualization of the FFM. Studied in a sample of 130 outpatients, clinical raters demonstrated reasonably good interrater reliability across personality profiles and the domains manifested good internal consistency with the exception of Neuroticism. The FFMSS ratings also evinced expected relations with self-reported personality traits (e.g., FFMSS Extraversion and Schedule for Nonadaptive and Adaptive Personality Positive Temperament) and consensus-rated personality disorder symptoms (e.g., FFMSS Agreeableness and Narcissistic Personality Disorder). Finally, on average, the FFMSS domains were able to account for approximately 50% of the variance in domains of functioning (e.g., occupational, parental) and were even able to account for variance after controlling for Axis I and Axis II pathology. Given these findings, it is believed that the FFMSS holds promise for clinical use.