By no means an undifferentiated mass of disposable workers, the new urban 'precariat' is traversed by hierarchies and loyalties that not only impact its exploitation, but also influence its prospects for collective mobilization. In this chapter, I illustrate this argument by considering workforce differentiation in the first decade of the twenty-first century in Chicago's formal day labor sector. This study is based on ethnographic fieldwork conducted from 2004 to 2006 involving participant observation in two different day labor agencies as well as several client-factories in Chicago's metropolitan, suburban, and exurban areas. In it, I analyze the internal workforce hierarchies that structure day labor agencies, specifically the importance of 'informal careers.' In each agency, the degree of inequality relates to the level and type of insecurity afflicting workers. I describe three typical conditions within this formally externalized workforce: that of 'casual temps,' who work for various agencies and at various factories; that of 'regular temps,' who are employed by the same agency but are sent to various client companies; and finally, that of 'permatemps,' workers who are employed by the same agency within the same factory for years.The ranks of this last category have swelled even as light-industrial staffing staffing has come to play in the role of an insurance scheme on Chicago's labor market, enabling client companies to 2 | P a g e employ undocumented immigrants without assuming the legal risks that would otherwise be involved.The paper shows how urban and ethno-racial segregation translates into the precarious workplace. As low-end staffing agencies consistently refuse to locate their offices in majority black areas, most African American job seekers are forced to travel daily to the city's immigrant port-ofentry neighborhoods. There, they commonly wait for work tickets alongside mostly undocumented Mexican and Central American applicants. As a consequence, the dispatch rooms of day labor agencies are among the few places in segregated Chicago where "unskilled" African American men and recent Latino immigrants can physically experience mutual economic competition.Following ethno-racial dynamics of inequality, however, this competition in securing employment has uneven consequences for different workers. African American workers tend to be less often and less durably used by client companies. To insure a maximum number of assignments and become 'regular temps' they are thus forced to construct loyalty relations with agency dispatchers.In contrast, a growing number of Latino migrant workers are joining the ranks of 'permatemps': they owe their job security to onsite supervisors, rather than agency dispatchers with whom they only keep contact irregularly. Industrial permatemps, even when undocumented, do not always remain in the lowest tier of the occupational ladder but sometimes benefit from informal careers through which they gradually gain positions of authority, wage increases, and, for some, paid vaca...