Abstract This article presents a history of the rise of 'people-centred' conservation in international environmental Non-Governmental Organisations (NGOs) during the global debt crisis of the early 1980s. In the mid-1980s, many NGOs embraced complicated financial arrangements called 'debt-for-nature swaps' to relieve the debt crisis and to promote environmental conservation in many developing nations. The swaps presented an opportunity for NGOs to promote environmental protection in the developing world in an era of crisis. Yet the implementation of the swaps reveal the challenges major environmental NGOs faced in incorporating new ideas about indigenous participation into their policies. The swaps came just as many of the leading environmental NGOs embraced market-oriented solutions to conservation issues and also adopted 'people-oriented' conservation strategies. Conservationists had a troubled history with indigenous peoples, but this article reveals how, by the late 1970s, many NGOs came to view them as allies in conservation efforts. Yet NGOs struggled to reconcile their desire for indigenous participation with the institutional demands of the swaps. Two brief case studies of swaps in Bolivia and Madagascar show how institutional and political challenges undermined a successful implementation of this new participatory vision. This article thus expands on scholarship of the relationship between environmentalists, native populations, and 'wilderness' ideology by showing how many leading environmental NGOs came to find a place for people in parks by the late twentieth century. It also highlights how the institutionalisation of the environmental movement into large NGOs both provided new opportunities to promote environmental protection and created constraints on individuals in implementing new ideas.