A mild deficit in executive functions has been hypothesized to be associated with attention deficit hyperactivity disorder (ADHD), with externalizing problem behaviors such as conduct disorder (CD) and with the vulnerability to alcoholism in sons of multi-generational alcoholics (SOMGAs). These three categories overlap, which raises concerns about the specificity of the hypothesized associations. In the present study, measures of executive functions (EFs) were tested in seventy-six 7- to 11-year-old boys: boys with ADHD but without a family history of addiction, SOMGAs, and controls. Specific deficits in EFs were found for boys with ADHD but not for SOMGAs. The association between a deficit in EFs and attention problems remained after controlling for externalizing problem behaviors, but not for the reverse. These results suggest that a mild deficit in EFs is specifically related to ADHD and that the deficits reported in boys with CD and in SOMGAs are due to relatively high attentional problems in these groups or due to other factors such as motivation.