The HHS Office of the Secretary is hosting the National Biodefense Science Board (NBSB) Public Meeting in Washington, D.C., on September 11, 2019. The purpose of the meeting is to gather information to develop expert advice provided by NBSB and guidance to the Secretary on scientific, technical, and other matters of special interest to HHS regarding current and future chemical, biological, nuclear, and radiological agents, whether naturally occurring, accidental, or deliberate.