Chapter 5 shows how the aftosa outbreak shaped the Mexican state’s efforts to modernize and regulate livestock from the 1950s to the 1980s. By disrupting existing methods of production and consumption, creating new technical capacities, and offering an example of effective state action, the crisis prompted officials to contemplate more ambitious state intervention. At the same time, the aftosa crisis offered painful lessons about the kind of political compromises and alliances – international and domestic – upon which government action rested. Along with the wane of Cardenismo, the Second World War, and the so-called Green Revolution, the aftosa campaign helps explain why Mexico’s developmental state took the shape it did, and illuminates its strengths, weaknesses, and contradictions.