In their previous book, Exchange in Oceania, anthropologist Per Hage and mathematician Frank Harary demonstrated that models from graph theory, a branch of pure mathematics, provide the essential basis for analyzing the great variety of exchange systems in Micronesian, Melanesian, and Polynesian societies. In this new book the authors extend these models and apply them to the analysis of communication, kinship, and classification structures in the island societies of Oceania, presenting the relevant topics from graph theory in a form accessible to the nonmathematical reader. The research problems include the formation of island empires, the social basis of dialect groups, the emergence of trade and political centers, the evolution and devolution of social stratification, the transformations of marriage and descent systems, the historical development of kinship terminologies, and the reconstruction of protosocieties.