Deborah Pacini-Hernandez. 2010. Oye Como Va!: Hybridity and Identity in Popular Music. Philadelphia: Temple University Press. Despite the fact that the number of Latin American immigrants and persons of Latin decent in the United States has increased significantly in the last two decades, mainstream mass media and academia have often neglected the contributions of these communities to US popular culture, and especially to music. However, this trend seems to be changing in the past few years with the production of documentaries such as Latin Music USA (aired in 2009 on PBS), and the increasing publication of academic books that focus on specific music genres performed by Latinos (eg. Ragland 2009; Rivera, et al. 2009; Washburne 2008). With Oye Como Va!, Deborah Pacini-Hernandez contributes to the literature on music and culture by blending sophisticated and comprehensive socio-cultural analysis of several music genres performed by Latinos such as rock, salsa, meregue, reggaeton, hiphop, and cumbia, along with basic histories of the genres and a tracing of their multiple interconnections. As an anthropologist, Pacini-Hernandez's is primarily concerned with the question of identity formation through popular music performance, recording, marketing, and reception. Since most of this music emerge from the crossroads of transnational flows of music and people from different nations in the Caribbean and the Americas, she provides a comparative and connective history of national and transnational music genres and their transformation in relation to cultural, social, economical, and political processes primarily within the United States, and also the Americas. Thus, the book's main interest groups would be those within academia, especially anthropologist, ethnomusicologist, and cultural studies scholars, interested in American and Studies, and those who study mass-mediated popular music in the United States; yet, it is accessible for the general reader. Pacini-Hernandez uses the term to name the people of Latin American descent who grew up in the United States; nevertheless, above all, she acknowledges the cultural heterogeneity of this population and the tensions within it. Throughout the book, she recognizes that these tensions often emerge from the fact that many Latinos belong to bilingual and racial minorities, and at the same time, are Americans and participants in US mainstream popular culture. This is not a fine-grained analysis of one musical genre in its immigrant communities, but rather a macroscopic view of music, acknowledging its diversity while unveiling another set of tensions that emerge from the different origins, population size, and visibility of the different communities in the United States. Pacini-Hernandez does not conflate the distinct nationalities and cultural heritage of Latin American immigrants and their descendants, but rather acknowledges their differences, similarities, and the tensions that complicate the general idea of a unified Latino cultural identity. Nonetheless, the book focuses primarily on the music and histories of Latinos whose music has had a significant impact in North American mainstream popular culture and elsewhere. Therefore, she focuses primarily on those Latinos of Puerto Rican and Mexican origin, the two groups with the largest presence in the United States; but Pacini-Hernandez also includes chapters on the music and experiences of recent migration waves of Dominicans and Colombians, and how their music has transformed and responded to previous waves of immigration. However, in a few chapters she touches on the role of Cubans and their music, both of which have had a great impact in American popular culture. In the first chapter, which serves as a theoretical introduction, Pacini-Hernandez approaches the question of identity formation through popular music. She states that music, a result of the crossing and in-betweeness of musical, geographic, racial, and ethnic boundaries, should be analyzed in terms of the multiple transnational flows of people and culture, the engagement of Latinos with US mainstream culture and music industry, and Latin American hybridity. …