I have long believed that city building is a story of implementation for which plans are but the foundation for debate and action, and that action is driven by politics, big and small. In writing this book, I aimed to tell the full story and to explain why things happened as they did. I wanted readers to understand how the forces of ambition and money and ego shaped the varied strands of this epic story.Rebuilding Ground Zero presented many tough questions: How would the need to commemorate the loss of thousands of lives be accommodated with the need to rebuild an economic future for Lower Manhattan? How would the rhetoric of defiance and resilience translate into concrete plans, architectural reality, political decisions, building priorities, and economic costs? And who had the power to execute the ideals and ambitions of rebuilding when property rights were split and political power fragmented? And where would the money come from to execute the grand ambitions of rebuilding Ground Zero?I sought to explain how big money and powerful public officials shape public-interest projects. Important as the planning and architectural phases of the rebuilding process were for cauterizing the immediate trauma of 9/11 by engaging the public with forward-looking visions, the critical decisions—program adjustments, cost compromises, and financial deals—were happening behind the scenes, in the off-the-record negotiations between the Port Authority of New York and New Jersey, as landowner, and real estate developer Larry Silverstein and his investment partnership, as owners of a 99-year lease on the Trade Center consummated just six weeks prior to 9/11.Those behind-the-scenes actions revealed a truism of public real estate development: one cannot build large without politics. At Ground Zero, politics intersected with economics in powerfully symbolic ways that reveal how cities in the United States get rebuilt.The book’s chapters take the reader from the tangled start and challenges to the plans for rebuilding through problems of execution to construction completion and opening ceremonies. In each chapter, I unravel the political and economic dynamics that shaped the process of rebuilding, including the billions in public money to ensure visible construction progress by the 10-year anniversary. Most importantly, I explain who had the power to execute the ideals and ambitions of rebuilding. In so doing, the story reveals how high-profile development projects get done in a post-Robert Moses world where political power is fragmented.