Despite the repressive military dictatorship in Brazil from 1964 to 1985, rural workers" trade unions flourished. During that period, 2,800 trade unions, representing 8 million laborers, were founded. Biorn Maybury-Lewis examines how union leaders carved out a place for themselves in the political order of the country, and how other progressive movements can succeed in comparable situation. Maybury-Lewis analyzes the institutional and political tools used by rural laborers, and what unionization meant for them. Though traditionally viewed as among the weakest member of society, rural workers proved able to confront, and even use to their benefit, the government"s stifling corporatist legislation. They succeeded in asserting themselves as a powerful minority for the first time in Brazilian history, in spite of the military regime"s suppressive Institutional Acts that suspended numerous civil and political rights and shut down Congress.In a period when similar authoritarian regimes in Chile and Argentina crushed social movements, Brazil"s rural workers mobilized on behalf of land, salary, and workplace disputes. While facing the potential threat of murder, rape, illegal arrest, kidnapping, slave labor, and other human rights violations, they succeeded by employing what Maybury-Lewis terms "the politics of the possible": the capacity to evaluate and dodge repressive measures, to keep alive the grassroots struggle, and to turn to their advantage institutional rules designed to suppress labor initiatives. Their story contributes to our knowledge of Latin America"s contemporary agrarian struggles as well as offering a case study of how social movements can withstand political repression in the most unlikely circumstances. Author note: Biorn Maybury-Lewis is Professor of Political Science at the University of Arizona.