<p>Waves transport energy through the atmosphere without transporting mass. Often excited in the troposphere, they can propagate horizontally and vertically over long distances, depending on the type of wave and the background atmosphere. The fastest atmospheric waves are (infra)sound and acoustic gravity waves. The list of possible reasons for the generation of these atmospheric waves is not short; here, we concentrate on natural hazards. Due to their comparatively high propagation speed, infrasound and acoustic gravity waves can contribute to or even improve early warning of natural hazards, even when measured at high altitudes. Traditionally, each scientific community—the one that deals with the neutral atmosphere and the one that addresses the ionosphere—usually works on its own. The aim of this manuscript is to bring together observations and results from both communities. The main challenges of the respective communities with regard to the use of these waves in the context of early warning of natural hazards are identified.</p>