Abstract: This study attempted to validate a theory posited by Fuster (1997), that the ADHD, Inattentive Type (ADHD/I) diagnosis is representative of the executive function deficits found in Dysexecutive Syndrome, such as with selective attention, working memory, verbal fluency, and planning, and that the ADHD, Combined Type (ADHD/C) diagnosis is representative of the executive function deficits found in Orbitofrontal Syndrome, such as with sustained attention and risk-taking. Forty-four adolescents between the ages of 12 and 17 were included in the study: 15 normal controls, 15 ADHD/I, and 14 ADHD/C. The adolescents were administered the Gordon Diagnostic System, the D-KEFS Verbal Fluency Test and Tower Test, The Dot Test (a measure of spatial working memory), and the Toronto Gambling Task (a measure of risk-taking). Multiple Discriminant Function Analysis was used to distinguish the groups based on task performance. The hypothesis from this study was not supported. While two significant functions were generated, the specific variables from which those functions were derived resulted in the direction opposite to that which was predicted. For instance, while theoretically Orbitofrontal impairment should have led to more attention errors of commission, it was the ADHD/I group that committed the most commission errors. Also, Dysexecutive impairment should have led to more attention omission errors, though it was the ADHD/C group that committed the most omission errors. Additionally, the risk-taking measure did not adequately contribute to distinguishing the ADHD/C group from the other two groups. It was also noteworthy that the overall means of all the executive functions assessed fell in the normal range, with the exception of the total rule violations on the D-KEFS planning measure, which occurred in the ADHD/C group. The author concludes that the executive function results from this study do not indicate that the ADHD/l diagnosis represents the deficits found in Dysexecutive Syndrome, or that ADHD/C diagnosis represents the deficits found in Orbitofrontal Syndrome. Further, a larger sample size may be needed to determine if the D-KEFS is sensitive enough to detect neuropsychological profiles among those with different subtypes of ADHD.