This issue on "Recent Research on Personality Behaviors” discusses diagnosis, epidemiology, etiology, outcome and treatment for these perplexing disorders. Topics include: Diagnosis: Dimensional diagnosis for PDs, Improving categorical diagnosis of PDs, Separating traits from personality disorders. Epidemiology: The community prevalence of PDs, The clinical prevalence of PDs. Etiology: Genetics of PDs, Neurobiological and imaging studies, The neurobiology of psychopathy, Child development and PDs. Outcome: The long-term outcome of PDs, Mechanisms of recovery in PDs. Treatment: Pharmacological and psychotherapeutic treatments, Managing suicidality, Future directions in PD research.