Analysis of the work of Florestan Fernandes (1920–1995) and Oracy Nogueira (1917–1996) on race relations in São Paulo in the context of the UNESCO project in which both participated sheds light on the link between the institutionalization of the social sciences in Brazil and the sociologists’ social engagement with subaltern sectors represented in the research on blacks. It also reveals that the two men held different views on the relationship between race and class. While in Fernandes’s work race was subsumed under class, in Nogueira’s it was an independent variable. Thus the UNESCO research called attention to differing interpretations of Brazilian racism.