Recent legal and political actions have challenged the use of race-conscious college admissions policies. Earlier research offers mixed evidence about the link between an institution's racial/ethnic composition (i.e., structural diversity) and the formation of close interracial relationships, so the present study examines this topic directly for several racial/ethnic groups. Within a large longitudinal data set, structural diversity is positively related to having close interracial friendships and a different-race romantic partner for White students, and no main effects of structural diversity are apparent for Black and Hispanic students. Moreover, structural diversity has increasingly positive effects at higher levels of campus diversity. (Contains 1 table.)