Transnational Mexican Migrants are the largest farm labor force in the United States. Problem drinking among their ranks is drawing increased public attention and concern in their new U.S. communities, but there is scant research that specifically addresses alcohol use among this population of migrants. The research on the Mexican American migrants, other migrants, Mexicans, and farmworkers in general is reviewed to identify etiological factors and data collection methods for future research on drinking among transnational Mexican migrants. This research reveals that situational factors (i.e., social isolation and peer influence) are highly associated with problem drinking among these migrants. It also demonstrates that binational ethnographic field methods are needed to study this "hidden" migrant population. Policies and programs that support the migration of families and offset social isolation appear to be a means for addressing the problem drinking.