Personality disorders are associated with fundamental disturbances of self and interpersonal relations, problems that vary in severity within and across disorders. This review surveyed clinician-rated measures of personality psychopathology that focus on self-other dimensions to explore the feasibility and utility of constructing a scale of severity of impairment in personality functioning for DSM-5. Robust elements of the instruments were considered in creating a continuum of personality functioning based on aspects of identity, self-direction, empathy, and intimacy. Building on preliminary findings (Morey et al., 2011 /this issue), the proposed Levels of Personality Functioning will be subjected to extensive empirical testing in the DSM-5 field trials and elsewhere. The resulting version of this severity measure is expected to have clinical utility in identifying personality psychopathology, planning treatment, building the therapeutic alliance, and studying treatment course and outcome.