This essay provides a panoramic view of transnational migration from the Dominican Republic to Puerto Rico. To begin, the author sketches the historical background of the exodus, underlining the ties between the two neighboring countries since the days of Spanish colonialism in the Caribbean. The main economic and political causes of the recent Dominican diaspora are also described. Second, the author examines the migrants' regional and socioeconomic origins in the home country as well as their settlement patterns and modes of economic and political incorporation into the host country. Third, several Dominican transnational practices in Puerto Rico are analyzed, particularly their community organization, through various political parties, hometown clubs, and other voluntary associations. Finally, the author identifies six issues for further study: the immigrants' cultural identity, second generation, transnational organizations, impact on public services, remittances, and businesses.