The Personality and Personality Disorders Work Group has proposed five specific personality disorder (PD) types for DSM-5, to be rated on a dimension of fit: antisocial/psychopathic, avoidant, borderline, obsessive- compulsive, and schizotypal. Each type is identified by core impairments in personality functioning, pathological personality traits, and common symptomatic behaviors. The other DSM-IV-TR PDs and the large residual category of personality disorder not otherwise specified (PDNOS) will be represented solely by the core impairments combined with specification by individuals' unique sets of personality traits. This proposal has three main features: (1) a reduction in the number of specified types from 10 to 5; (2) description of the types in a narrative format that combines typical deficits in self and interpersonal functioning and particular configurations of traits and behaviors; and (3) a dimensional rating of the degree to which a patient matches each type. An explanation of these modifications in approach to diagnosing PD types and their justifications-including excessive co-morbidity among DSM-IV-TR PDs, limited validity for some existing types, lack of specificity in the definition of PD, instability of current PD criteria sets, and arbitrary diagnostic thresholds-are the subjects of this review. © 2011 The Guilford Press.