Based upon analyses of interview data collected from twenty-six clinician respondents, this study explores two facets of clinician uncertainty related to the diagnosis and treatment of attention deficit hyperactivity disorder (ADHD) in children. First, this study explores clinician reservations about the diagnostic validity of ADHD as it is described by the American Psychiatric Association (1994) in DSM IV. Second, this study explores clinician ambivalence regarding the physical and social-psychological side-effects of stimulant medications, such as Ritalin. In applying the sociological discussions that address uncertainty in clinical settings and through reviewing a sizable cross-section of the popular and research-oriented literature demonstrating the contentious nature of the ADHD phenomenon, this study illustrates that clinicians do not practice within a vacuum, but are instead largely affected by the marked scepticism that surrounds ADHD. In being affected by this scepticism, it is concluded that clinicians who assess and treat ADHD are autonomous in how they interpret the diagnostic and treatment protocols for this mental disorder.