An enduring question is the nature of the complex interplay between the mind and the body. The Adult Psychopathology, Personality, and Treatment (APPT) Lab approaches this question with basic and applied research methods that test assumptions about personality, psychopathology, and health. We use state-of-the-art structural modeling, psychometrics, and psychotherapy to address the contributions of personality traits to both adaptive and maladaptive functioning. This dimensional approach to psychopathology suggests these traits are risk factors for negative mental and physical outcomes. Neuroticism/Negative Emotionality (N/NE) is a trait, risk factor that is shared by all the emotional disorders, a taxonomy that transcends traditional diagnostic categories. The focus of our research is on the emotional disorders that are characterized by distorted perceptions of health and body (e.g., somatic symptom, body dysmorphic and anxiety disorders); these frequently present in medical settings and are effectively treated in an integrated primary care context.