The Department of Homeland Security (DHS) must continue its vital mission to protect the Nation even when faced with the possibility of an incident involving a biological agent or a pandemic causing widespread illness and death. Either of these events could greatly hamper DHS’s ability to meet its mission. In 2010, DHS established its Medical Countermeasure Program (MCM Program) to ensure continuity of operations. The DHS MCM Program stockpiles antibiotics, antivirals and limited radiological/nuclear countermeasures to protect the DHS workforce and those under DHS care and custody. The program has since evolved and now has over 600 Points of Dispensing (PODs) nationwide to provide required medications anywhere in the United States, from remote rural border areas to densely populated urban areas. In addition to working to protect its workforce and those under its care and custody, DHS partners with other federal agencies, as well as State, Territorial, and Tribal Health Organizations to safeguard the Nation and ensure a comprehensive plan for medical countermeasure preparedness. DHS is a critical member of the Public Health Emergency Medical Countermeasure Enterprise (PHEMCE), and the DHS Chief Medical Officer represents the Department on the PHEMCE Advisory Council. As a key partner of the PHEMCE, DHS helps to facilitate collaborative activities and inform federal decision making related to medical countermeasure preparedness. These activities include identifying needs to protect Americans, developing strategies to address MCM gaps and making both strategic and policy recommendations to the Department of Health and Human Services. The DHS MCM Program’s work in both of these areas is key to secure the Nation from the many threats it faces. It will continue to grow to meet the evolving risks and employ the latest tools prevent, mitigate, or treat the adverse health effects of an intentional, accidental, or naturally occurring public health emergency.