DSM-5 marks a watershed moment in the history of official psychiatric classification systems because it is the first DSM to feature an empirically based dimensional model of personality pathology. Relative to DSM-IV, DSM-5 is better connected with assessment research because it encompasses an empirically-based model of maladaptive personality traits, and an associated assessment instrument, the Personality Inventory for DSM-5 (PID-5). Nevertheless, much of DSM-5 remains constrained by the psychiatric proclivity to conceptualize psychopathology in terms of numerous putatively discrete categories, despite extensive evidence to the contrary of this conceptualization. Although numerous political and scientific challenges remain, working to enhance the connection between Psychiatry and quantitative assessment research will ultimately enrich both areas. This talk will review recent research on the PID-5, and discuss how this stream of research can influence how we approach problems in psychiatric classification.