Tore C. Olsson‘s Agrarian Crossings: Reformers and the Remaking of the US and Mexican Countryside (Princeton University Press, 2017) tells a remarkable and under-appreciated story. It’s about how, in the 1930s and 40s, a group of reformers in the US and in Mexico undertook projects to transform the rural worlds of their respective countries in the name of social justice and agrarian productivity. Olsson demonstrates how closely the histories of Mexico and the American South in particular paralleled one another, and how parallel histories yielded parallel problems, including mass rural poverty, landlessness, and economic deprivation. Whether in Mississippi or Michoacan, Tennessee or Tabasco, the rural masses saw few tangible benefits in the economic miracle heralded by boosters in Atlanta and Mexico City, Professor Olsson writes. And so in that decade historians sometimes like to call the long 1930s, Mexican and US reformers crossed the border again and again, to share models and ideas, and to undertake projects of rural revitalization through varying methods and with varying results. Olsson’s book recovers a world in which like-minded Mexicans and Americans worked together, toward what they hoped would be a more just world, in concert and in solidarity. Tore C. Olsson is Assistant Professor of History at the University of Tennessee, Knoxville. Monica Black is Lindsay Young Associate Professor of History at the University of Tennessee, Knoxville.