The judicial doctrine of preemption allows federal or state governments to restrict the ability of state or local governments, respectively, to regulate in a given area. Industries whose products create substantial public health risks have begun to promote preemptive legislation which prevents the lower levels of government from adopting strong public health protections. This article discusses the implications of preemptive legislation concerning three of the most harmful products available in America: tobacco, firearms and alcohol. These examples illustrate the potential danger that preemptive legislation poses to efforts to prevent illness, injury and death caused by these products.