Objective: Although a number of studies demonstrate that children with ADHD do not attribute their behavior to taking medication, it remains unstudied whether adolescents, who have a longer history of taking medication for ADHD, show performance attributions to medication. Method: A sample of 46 adolescents completed daily attributions for success or failure as a part of their participation in a summer treatment program with a double-blind, placebo-controlled assessment of methylphenidate. Results: Results demonstrated that adolescents with ADHD did not reliably discern active medication from placebo, rarely attributed their performance to the pill, and showed no differences in attributional style as a function of medication status. Conclusion: These data indicate that adolescents with ADHD may possess inaccurate beliefs about the effect of stimulant medication on their behavior. (J. of Att. Dis. 2013; XX(X) 1-XX)