To address these gaps in the literature, this paper uses data from a nationally representative sample of U.S. adults to examine the associations of internalizing and externalizing psychopathology with the likelihood, expression and course of DSM-IV alcohol dependence and to determine whether these associations differ for men and women. The specific aims of the paper are to determine, in a nationally representative sample of U.S. adults: 1) whether the distribution of internalizing and externalizing psychopathology in lifetime alcoholics varies by gender; 2) whether men and women differ in the extent to which lifetime alcohol dependence is associated with lifetime internalizing and externalizing psychopathology, other factors held constant; 3) whether the potentially mediating effects of being a drinker and volume of consumption affect gender differences in comorbidity; 4) whether the expression and course of alcoholism among individuals with different types of psychopathology vary by gender, and 5) whether the associations of internalizing and externalizing psychopathology with the expression and course of alcoholism vary by gender after controlling for potential confounders.