Geography professor Kaplan (Kent State Univ.) seeks to extend understanding of ethnicity through the heretofore largely ignored lens of geography and space. He begins by tracing the evolution of the conceptualization of ethnicity, noting seminal contributions from sociology, anthropology, psychology, history, and political science, among other disciplines. However, he is particularly interested in examining “how ethnicity plays out on the ground.” Kaplan comprehensively explores spatial boundaries between groups, taking into account geographical context and its intersection with such factors as class, gender, and age. He also addresses motives for (and causes of) ethnic segregation, be it externally driven from intergroup exploitation and conflict, or internally rooted in voluntary seclusion. Acknowledging the segregation that exists, the author presents comprehensive research on both the negative and positive consequences of ethnic concentration, leaving it to readers to ultimately decide if such segregation is functional or dysfunctional for society. Finally, Kaplan envisions the future of ethnicity, taking into account the latent consequences of contemporary social forces including transnationalism, urbanization, and globalization. Overall, a well-researched and unique contribution in the ever-salient field of ethnicity and ethnic relations. Summing Up: Highly recommended. Graduate students/faculty/professionals.