Biological surveys starting in the 1950s provided clear evidence that the Itombwe Massif, located in eastern Democratic Republic of Congo, is one of the most important areas for conservation in Africa. Further surveys in the mid 1990s and early 2000s showed key species were still present and could be conserved. Following a report on these surveys the Ministry of Environment established the Itombwe Reserve in 2006 without consulting local communities who have legitimate customary rights to reside within the area and use the region's natural resources. Although creating the Reserve was within the government's legal authority, its establishment violated the rights of the people there. Here we report over a decade of work by a consortium of international and national human rights and conservation NGOs, the local communities and the protected areas authority (Institut Congolais pour la Conservation de la Nature), to remediate this taking of customary rights. Starting in 2008 these partners began a participatory process with all 550 villages within and around the boundary of the Reserve. Using a community resource use mapping approach, developed from best practices, the team helped communities determine the boundary of the Reserve, and then pilot participatory zoning to identify zones for settlements, agriculture, hunting, gathering of non-timber forest products, and conservation. This process secured the customary rights of long-term residents in the Reserve and protected their lands from being taken by non-rights holders. As a result of this work the use rights of communities were largely restored and the communities agreed on 23 June 2016 to formalize the boundaries of the renamed Itombwe Nature Reserve.