There is accumulating evidence that clients with personality disorders show poorer treatment outcomes for Axis I disorders, including anxiety, mood, and substance use disorders (Reich, 2003; Vaglum & Ravndal, 2003). In a recent review of the research literature on this topic, Reich (2003, 400) concluded, “Pathological personality traits are a negative predictor of the outcome of treatment for anxiety and depressive disorders — a conclusion that is not confined to one set of personality disorder traits or one cluster of traits.” Possible explanations for the negative treatment effects cited by Reich (p. 390) include greater likelihood of personality disorder clients dropping out of treatment, poorer treatment compliance, interpersonal difficulties with treating clinicians, and clients reporting more side effects from psychotropic medications.