Manu National Park was founded in 1973 on a profound contradiction: The “untouchable” core area is, in fact, the homeland of a large indigenous population, including the Matsigenka (Machiguenga). Some view the Westernization of native communities living in protected areas as a threat to biodiversity conservation and suggest that such populations should be enticed to resettle outside parks. Here, we present an overview of the indigenous populations of Manu, outline the history of the park and its anthropological policies, and discuss evolving park-Matsigenka conflicts as well as areas of common interest. Analysis reveals that resettlement has no political, legal, or practical viability. Thus, given the options available, we propose that long-term biodiversity conservation can best be achieved through a “tenure for defense” trade: indigenous communities receive explicit benefits (e.g., infrastructure and service investments, employment opportunities, or economic alternatives such as ecotourism) in exchange for helping to defend the park against incursion and managing vulnerable resources such as game animals.