In this article, we describe ways in which different socioeconomic and racial/ethnic groups might fare differently in an infl uenza pandemic, on the basis of current knowledge of social factors that shape exposure and vulnerability to infl uenza virus and that infl uence the timeliness and adequacy of treatment among those who become ill. We also discuss policy decisions, made either before or during a pandemic, which might differentially affect risk for illness or death for those of low income and of specifi c racial/ethnic groups. Our purposes are to 1) call attention to potentially major and avoidable social disparities in suffering and death during an infl uenza pandemic and 2) highlight the importance of including in pandemic preparedness plans targeted strategies for minimizing or avoiding these social disparities. The following discussion is not meant to be exhaustive; rather, it is meant to provoke refl ection about how potential disparities in the effects of an infl uenza pandemic might be reduced or eliminated through appropriate planning and implementation of clinical and public health activities.