This book argues that, collectively, unions can help shape how the rules governing the global economy are made.How did NAFTA, a neoliberal trade agreement considered the concrete manifestation of globalization processes in North America, catalyze solidarity among U.S., Canadian, and Mexican unions and help erode union policies and discourses rooted in racism? And why did some labor unions more readily engage in transnational collaboration and embrace internationalism than others? By showing how transnational laws and governance institutions constrain and expand transnational social movements, the book provocatively suggests that globalization need not undermine labor movements: collectively, unions can help shape how the rules governing the global economy are made.How did NAFTA, a neoliberal trade agreement considered the concrete manifestation of globalization processes in North America, catalyze solidarity among U.S., Canadian, and Mexican unions and help erode union policies and discourses rooted in racism? And why did some labor unions more readily engage in transnational collaboration and embrace internationalism than others? By showing how transnational laws and governance institutions constrain and expand transnational social movements, the book provocatively suggests that globalization need not undermine labor movements: collectively, unions can help shape how the rules governing the global economy are made.When NAFTA went into effect in 1994, many feared it would intensify animosity among North American unions, lead to the scapegoating of Mexican workers and immigrants, and eclipse any possibility for cross-border labor cooperation. But far from polarizing workers, NAFTA unexpectedly helped stimulate labor transnationalism among key North American unions and erode union policies and discourses rooted in racism. The emergence of labor transnationalism in North America presents compelling political and sociological and puzzles: How did NAFTA, the concrete manlÓ: