The recent lowering of some obstacles to the migration of Micronesians to Guam has resulted in a sudden influx of migrants. In a short time, Guam has experienced many of the impacts associated with large scale migration on population growth, provision of services and the issue of ethnic assimilation. An extensive demographic profile of newly settled migrants is presented, followed by a discussion of future implications. Micronesian migration is expected to grow, encouraging the formation of nucleated ethnic communities, a sizeable working class, and social costs and potential ethnic conflict that will draw increasing attention from the Guam government.