When i was invited to participate in this special issue, it was suggested that I meditate on a long-term research project I did in collaboration with the public-health scholar María Gudelia Rangel Gómez and the demographer Armando Rosas Solís, on people working in prostitution in Tijuana, a city on the United States–Mexico border. That work began in the 1990s and continued through the middle of the last decade, producing three articles on women and two on transvestite sex workers.1 Looking over the raw survey data and interview transcripts in preparation for this article impressed on me once again how these people are engaged in what Saskia Sassen calls “survival circuits” between the global South and global cities like Los Angeles and Tijuana, some of them located in the North, some not. These sex workers come from all over the Mexican Republic, migrating to Tijuana—a city both Third World and global—for reasons of economic necessity, and often their stories include low-wage labor in the United States as well as participation in the informal economy in the northern border area to supplement (or mask) their primary income. Regardless of other factors, the people we surveyed and interviewed express an understanding that to live means to work and that the work they are doing is precisely work: not organized labor, not a career path. They know that their bodies are made marginal or invisible and their voices go unheard. At the same time, while their lives may seem unimaginably harsh to many of us, in their stories they often present themselves as rational actors, making the best choices they can from among limited options for themselves and their families.