In this article we examine how partner choice and strategies of social reproduction among the Wampar of northeastern Papua New Guinea are implicated in currently pressing questions about the future of Wampar as a socio-cultural unit. We use long-term qualitative and quantitative data based on fieldwork and census surveys conducted between 1954 and 2013 from the village of Gabsongkeg to analyse temporal and spatial patterns of partner choice. We are especially interested in interethnic marriages and their effects on group boundaries and group identities, given a pre-existing pattern of ethnic endogamy. Our results show that intermarriages between Wampar and non-Wampar have constantly been rising; in younger marriage cohorts some 60% of Wampar individuals are intermarried with partners of other ethnic identities. The data reveal that local and historical particularities inflect partner choices in ways that impact on settlement patterns, modes of engagement with the economic institutions of the modern state and, ultimately, the taken-for-granted nature of the identity inhering in the name “Wampar”; these impacts, in turn, increase the likelihood of interethnic marriage and precipitate questions about the rights attaching to local corporate identities under conditions where land is increasingly related to its commodity values.