OBJECTIVE The purpose of this study was to examine differences in heavy alcohol use and alcohol-related negative effects among U.S. military personnel stationed in different world regions and to examine factors that may account for regional differences. METHODS Data were drawn from the 1998 Department of Defense Survey of Health Related Behaviors among Military Personnel, which had a large representative sample of active-duty U.S. forces. Heavy alcohol use and related negative effects (severe consequences, productivity loss and alcohol overuse) were examined in four regions (Asia, Europe, Hawaii and continental United States; N = 17,154; 86% men) using multivariate logistic regression models that controlled for demographic factors. RESULTS U.S. military personnel stationed in Asia were significantly more likely to be heavy alcohol users than personnel stationed in the other regions. Productivity loss was also significantly greater in Asia, whereas severe consequences and alcohol overuse were not. Possible explanations for the findings include local regional culture, availability of alcohol, freedom from restraints, response to stress, military culture and selection effects. CONCLUSIONS Heavy alcohol use of military personnel varies by region of assignment and may be attributable to a variety of factors. Future studies need to examine regional alcohol use in greater detail and to include measures specific to potential explanatory domains to permit a more complete understanding of underlying causal mechanisms of heavy drinking by U.S. forces in Asia. Current findings suggest that alcohol use prevention and early intervention programs should be tailored to take account of regional differences.