Mark F. Lenzenweger, PhD, is Professor of Clinical Science, Cognitive Psychology, and Behavioral Neuroscience in the Department of Psychology at the State University of New York (SUNY) at Binghamton and Adjunct Professor of Psychology in Psychiatry at the Weill Medical College of Cornell University, New York City. He also directs the Laboratory of Experimental Psychopathology at SUNY/n-/Binghamton, where he conducts research and teaches on personality disorders, schizophrenia, schizotypy, and statistical methods. John F. Clarkin, PhD, is Professor of Clinical Psychology in Psychiatry at the Weill Medical College of Cornell University and Director of Psychology and Co-Director of the… Personality Disorders Institute at New York/n-/Presbyterian Hospital. His academic writing and research have focused on the phenomenology of the personality disorders and the treatment of patients with borderline personality disorder.