This report discusses the Project BioShield Act (P.L. 108-276), In 2004, passed by Congress to encourage the private sector to develop medical countermeasures against chemical, biological, radiological, and nuclear (CBRN) terrorism agents and to provide a novel mechanism for federal acquisition of those newly developed countermeasures. This law provides three main authorities: (1) relaxing regulatory requirements for some CBRN terrorism-related spending, including hiring personnel and awarding research grants; (2) guaranteeing a federal market for new CBRN medical countermeasures; and (3) permitting emergency use of unapproved countermeasures.