We explored the validity of the Psychopathology Five (PSY-5) facet scales of the adolescent version of the Minnesota Multiphasic Personality Inventory (MMPI-A; Butcher et al., 1992) in an adolescent inpatient psychiatric sample (N = 662) through a series of correlational analyses with self-report measures, therapist ratings, and chart review variables. Consistent with previous research with PSY-5 parent scales, externalizing symptoms were most clearly related to Hostility and Delinquent attitudes facet scales; internalizing symptoms were most clearly related to the presence of high Neuroticism facet scales and Low Drive/Expectations facet scales; and bizarre features and psychotic symptoms were most strongly related to both the Psychotic Experiences and Odd Mentations facet scales as well as the Low Drive/Expectations facet scales. These findings lend some support for the use of these facet scales as useful adjuncts to the PSY-5 parent scales.