Concerns about the (lack of) diversity of the U.S. teacher workforce--and, in particular, the mismatch between the demographics of the teacher workforce and the nation's students--are not new. Recruitment of minorities into teaching has long been a policy goal, particularly in districts with large percentages of minority students (Dometrius & Sigelman, 1988; Kirby et al., 1999). As then Secretary of Education Richard Riley put it nearly two decades ago, "Our teachers should look like America" (Riley, 1998, p. 20). Despite this rhetoric, relatively little progress toward ensuring that the diversity of the teaching workforce reflects the diversity of the student body in U.S. public schools. Should school districts seek explicitly to recruit minority teachers? The answer to this question depends in part on one's view of the importance of providing employment opportunities to traditionally underrepresented groups and how this relates to efforts to create a culturally diverse and culturally sensitive teacher labor force. It also depends on whether minority teachers are more effective in educating some types of students. This report provides an overview of both the theoretical arguments and the empirical evidence supporting the importance of teacher workforce diversity. It also places the magnitude of these empirical findings in context and discusses some potential trade-offs to diversifying the teacher workforce.