The issue of transborder mobility posed a dilemma for U.S. labor organizations and for border communities that embraced workers, customers, and family connections from Mexico. Labor leaders including Ernesto Galarza of the National Farm Labor Union (NFLU) and César Chávez of the United Farm Workers (UFW) had to find ways of protecting U.S. citizen workers and yet humanely addressing the plight of resident aliens, permitted commuters, and undocumented workers from Mexico. Their strategies involved knowledge production and had to accommodate emotions. The article focuses on the Imperial-Mexicali borderlands, 1950s–1970s.