This ethnographic article discusses how race emerges between discourses of class and space at the University of the State of Rio de Janeiro. Following a legal decision, this academic institution was required to implement racial quotas to combat social exclusion and raise the number of ‘black’ students in public higher education. A crucial question is whether such racially based policies help redress social inequalities, or whether they actually increase discrimination by reifying ‘racial’ differences in Brazil. I argue that the social diversity promoted by quotas at the university stresses certain urban tensions and unequal dynamics that come to be reflected within the university. However, it also reveals novel and positive paths by which policies can negotiate these contrasts.