Book excerpt: "In Sentinel Musicians of the Ethiopian American Diaspora, Kay Kaufman Shelemay shares more than forty years of research among Ethiopian musicians in the midst of a widespread and evolving diaspora. Beginning on the eve of the Ethiopian revolution in 1974 all the way up to the present day, Shelemay follows musicians as some leave Ethiopia for the US, setting up essential networks of support in cities such as New York, Boston, and Washington, DC. Throughout this profound transition, Shelemay shows how Ethiopian musicians serve a critical function in social and political life by both safeguarding community identity and challenging authority within Ethiopian society. She coins the term "sentinel musicians" to express musicians' double capacity to guard culture and guide it through periods of change, transforming the world around them under political pressures and during times of extreme social stress. While musicians held this role in Ethiopian culture long before the revolution began, it has taken on new meanings and contours in the Ethiopian diaspora. Some sentinel musicians have quite literally led the way as they migrated to new locales, establishing transnational networks, founding new institutions, and undertaking numerous initiatives in community building. Ultimately, Shelemay shows that musicians are uniquely positioned to serve this sentinel role as guardians and challengers of cultural heritage"--