Since the second edition of this authoritative text was published in 2002, the research base supporting the Five-Factor Model (FFM) of personality disorder has more than quadrupled. As a result, the vast majority of this volume is new. In the upcoming fifth edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-V), the major innovation for the personality disorders will likely be a shift from the classic syndrome-based approach to a dimensional description approach. The new approach views personality disorder as a collection of maladaptive variants of normal personality traits. Whether a clinical disorder is present depends on whether an individual experiences significant functional impairment. Because this approach allows clinicians to describe each patient in terms of the personality traits most relevant to his/her experiences and dysfunction, the result is a more accurate diagnosis and more effective treatment. This book explains how personality disorders can be understood from the perspective of the FFM, the most heavily researched and empirically supported dimensional model of general personality structure. The chapters summarise the conceptual and empirical support for the FFM, including the dimensional description of specific personality disorders and the application of the model for assessment and treatment. Case studies are also provided. The volume is an essential reference for clinicians, researchers, and graduate students who work with personality disorders. No other currently published text is as fully informed or as closely coordinated with the likely forthcoming DSM-V personality disorder nomenclature.