The CSIS Commission on Countering Violent Extremism, cochaired by Tony Blair and Leon Panetta, was formed to develop a comprehensive and actionable blueprint to combat the growing appeal of violent extremism in the United States and abroad. Specifically, the Commission considered what the next U.S. administration must do, in close collaboration with governmental and nongovernmental partners, to diminish the appeal of extremist ideologies and narratives. This report is the culmination of the Commission’s work.