Cyber Storm (CS), the Department of Homeland Security’s (DHS) capstone national-level cyber exercise series, provides the framework for the most extensive government-sponsored cybersecurity exercises of their kind. Mandated by Congress, these exercises are part of the Department’s ongoing efforts to assess and strengthen cyber preparedness and examine incident response processes. DHS uses the findings to support improvement to collective cyber incident response capabilities. The exercises also strengthen information sharing partnerships and build relationships among federal, state, international, and private sector partners.