In the past twenty years, growing percentages of ethnic minorities in the United States have led scholars to pay increased attention to the issue of diversity. While a number of convincing normative arguments for inclusion and integration have been advanced in the literature, very little research using public organizations as the unit of analysis has sought to understand the empirical impact of workforce diversity on work-related outcomes. Much of the public administration research on diversity stems from the normative view that any diversity leads to positive consequences, but theory from social psychology and organizational behavior research suggests that diversity can result in either positive or negative consequences, depending on the task at hand. This study contributes to the literature on diversity in public organizations by testing the impact of ethnic diversity and representation on a series of performance outcomes. I use data from the public education policy setting to test hypotheses linking ethnic diversity and representation among both public managers and street-level bureaucrats to organizational performance. The data consist of all Texas public school districts for each year between 1995 and 1999, and the models control for a number of environmental resources and constraints that tend to correspond to performance in public schools. The results of the study indicate that ethnic diversity among street-level bureaucrats corresponds to lower organizational performance, while ethnic representation among street-level bureaucrats corresponds to higher organizational performance. That is, the more ethnic variation among teachers, the lower the performance in the school district, but if that variation simply matches the variation of the students in the district, the schools perform better. Manager diversity and representation were unrelated to organizational outcomes across the board, leading to the conclusion that, when it comes to representational impacts, street-level bureaucrats are much more influential than managers.