This research centered on warning dissemination and community response and included three components. First, field studies of communities that experienced either flash floods, hurricanes, tornadoes, or earthquakes were conducted. This involved researching organizations within the community. Additionally, the second component involved surveying 200 households in each community. The central focus of the research of the organizations was the effectiveness of warning dissemination while preparedness and response were the foci of the community survey component. Questionnaires with the community and interviews with organizations were designed incorporating the situations before and after the hazard. The third component was laboratory simulations of how message content, prior experience, timing, and social factors influenced the public’s response to warnings. Field and laboratory results matched well with prior research findings with prior knowledge being a key determinant in response.