In 1885, a German physician named Heinrich Hoffman wrote about some interesting patients that he saw in his practice, including the case of “Fidgety Phil,” which he found particularly intriguing (Stewart, 1970). This description is commonly regarded as the first important reference to a boy with hyperactivity. Because Phil could not remain still for any significant period of time, he exhibited significant management difficulties and proved to be very frustrating to those who came in contact with him. Since that time, hyperactivity has been considered to be among the most common, and troubling, behavioral symptoms of childhood.