Smokes, obscurants, and riot-control agents constitute a diverse group of chemical compounds that are released into the environment during training exercises. Concern has been expressed over the use of these compounds and how they may affect threatened and endangered (T&E) species that reside on military installations. This report (Volume 1 in a series) contains an overview of studies and investigations on the effects and impacts of military smokes, obscurants, and riot-control agents on T&E species. It also discusses the primary laws and regulations of interest and importance to the military services when using these agents on training lands.