A paper by Richard Schultz, spring 2005 fellow, analyzes the debate surrounding the FCC’s Diversity Index and explores the question of how to best measure media diversity. Given the centrality of media diversity as a longstanding policy goal of the FCC, the question of what constitutes diversity must be at the heart of any attempt to develop appropriate rules governing media ownership. The paper consists of three sections. The first addresses the meaning of media diversity and the complications that conceptualizing media diversity pose for developing a noncontestable measurement system. The second section analyzes the controversy that enveloped the FCC’s attempt to develop its Diversity Index. The final section offers some concluding comments.