A congressional mandate to dispose of the current US stockpile of lethal unitary weapons (Public Law 99-145, Department of Defense Authorization Act of 1986) has international implications and is responsible for a recent major assessment of available disposal alternatives. Eight installations in the continental United States currently host aging stockpiles of chemical warfare agents. The stockpiles are described, the toxicology and physical properties of each agent are characterized, disposal options considered by the US Army are identified, and the role of a programmatic health and environmental assessment in the decision-making process is outlined. Critical findings are that existing community emergency planning and preparedness are inadequate and that communication of risk information requires significant improvement. Measures are under way to address these needs. However, timely disposal of the stockpile entails less of a hazard than continued storage.