All over Mexico today people are celebrating National Maize Day, with feasts and festivities honoring the country’s treasured crop. They are also commemorating the 12-year anniversary of the judicial ruling that put a stop to experimental planting of genetically-modified corn in the country, the product of a class-action suit filed by an upstart coalition of farmer, environmental, and consumer groups known as the Demanda Colectiva.

That campaign, which I documented in a chapter of my book Eating Tomorrow, withstood a blizzard of appeals by Monsanto and other multinational seed companies. It stopped GM corn cultivation in its tracks, over the opposition of the Mexican government at the time. It later led to a presidential decree by a new government that banned GM corn cultivation and direct consumption in tortillas and a vigorous if ill-fated defense in a trade dispute filed by the U.S. government. Despite that ruling, the Mexican government enshrined the ban on GM corn cultivation in its constitution.

In the course of researching the issue for my book I had my own close encounter with the genetically-modified minds of Monsanto, a revealing five-hour interview with six company executives in their Mexico City headquarters in 2014. I documented the exchange in my book and in a three-part series of articles that I share here in tribute to Mexico’s vigorous and successful defense of its precious native crop.