In this book, the authors discuss new research on personality disorders including grandiose and vulnerable narcissism and the nature of Narcissistic Personality Disorder (NPD); an examination of personality pathology with the five factor model and personality psychopathology-5; forensic and non-forensic mental health nurses’ perceptions in relation to their clinical or management focus for those with a diagnostic label of personality/psychopathic disorder; and the Millon Clinical Multiaxial Inventory-III (MCMI-III) and the Personality Disorder Questionnaire-4+ (PDQ-4+) in a mixed Italian psychiatric sample.