Since the U.S. Supreme Court ruled that racially segregated schools were unconstitutional in 1954, researchers have been interested in interracial relations in schools. The current study extends previous research in this area by focusing on how schools influence both interracial friendliness and interracial conflict. Three main theoretical perspectives guide the research: macrostructural theory, contact theory, and group threat theory. Data were drawn from the High School Effects Study that collected information from students, teachers, parents, and principals concerning race relations in schools in the 30 largest Metropolitan Statistical Areas. Results of multilevel model analyses indicated some support for all three theoretical perspectives. Specifically, school integration was found to increase perceptions of both interracial friendliness and conflict, with perceptions of conflict increasing more rapidly. Factors found to aggravate racial relations included segregated tracks, fewer minority teachers, less group work, and segregated extracurricular activities. Moreover, it was observed that in biracial schools with equally-sized groups, students were likely to avoid interracial contact. These findings suggest that when greater integration is attempted in schools, more conflict than friendliness will be the likely outcome. School administrators are encouraged to take proactive steps to minimize perceptions of interracial conflict. More research is warranted on the way in which school integration has been implemented. Figures, tables, references