The background chapter titled "Adults With ADHD: An Overview," by Paul Wender (a pioneer in adult ADHD research), Lorraine Wolf, and Jeanette Wasserstein, establishes the basic history, phenomenology, comorbidity, and differential diagnosis of adult ADHD. "A Nosology of Disorders of Attention," by Allan Mirsky and Connie Duncan, provides a neuropsychological layout of attention, including a useful description of the commonly used assessment instruments and measurements and the etiology of attentional problems in disorders other than ADHD.