The informal U.S. deadline for Iran’s negotiating a compromise agreement with the international community that would constrain its expanding nuclear program has expired. Now the Obama administration, along with foreign governments, must decide how to respond to Iran’s continued development of the capacity to enrich uranium for nuclear fuel and, potentially, nuclear weapons. The failure of Iran to respond to American offers of engagement raises important questions about U.S. efforts to halt nuclear proliferation: Has Iran’s behavior undermined the effectiveness of the Nuclear Non-Proliferation Treaty? If engagement continues to fail, what other viable policy options does the U.S. have? How do domestic politics in Iran and regional politics in the Persian Gulf affect the range of acceptable solutions? This panel discussed U.S. options in the coming months and debated the merits of various proposed approaches, including continued engagement, increased sanctions, and military action.