In the context of a global war on terrorism experts have focused on the potential for a bioterrorist incident to cause widespread health and psychological consequences. Preparation is critical to improving the U.S. response to future bioterrorist incidents and educating the public is recognized as a vital part of this preparedness effort. Under a grant from the U.S. Veterans Health Administration (VHA), researchers from a network of VA health care and research facilities initiated a program to develop and evaluate educational materials for veterans--including those with mental illness. This article describes the results of a series of focus groups with three veteran subpopulations of interest to characterize their concerns and information needs and summarizes the insights gained that helped guide materials development.