During the terrestrial survey of the “Our Planet Reviewed” project in Papua New Guinea we created a bridge between biodiversity research, capacity building and nature conservation. The scientific aim of the project was to estimate, for the first time, the biological diversity generated by altitudinal turnover of insect species. The project was set up by the Natural History Museums of Brussels (RBINS) and Paris (MNHN), the NGO Pro-Natura International, the French IRD and, as local partners, the New Guinea Binatang Research Center (BRC) and the University of Papua New Guinea. Half of the core scientific team (ca 50 persons) was made of local research assistants and the other half of international biodiversity experts. Local research assistants (called paraecologists and parataxomists) were recruited in local communities, trained by BRC and supervized by the international experts. Locals were involved in sample collection, sample pre-sorting and received training and salary. This not only speeded up sample collection, but simultaneously supported nature conservation as the locals had means of income other than from commercial logging. We also paid land-use fees to land owners as compensation for collecting plants and animals in their forest plots. Conservation initiatives by local communities were further supported by funds from private sponsors raised by BRC. Funds were also collected to allow local scientists to visit overseas laboratories and to participate to international conferences. To summarize, large-scale biotic surveys are not only essential to understand the functioning of complex tropical ecosystems where biodiversity is highest but can also be important drivers of capacity building and nature conservation. Associated movie: “In the treetops of Papua New Guinea”. Director: Maurice Leponce. Author: Maurice Leponce & Gildas Corgnet, 2015, HD, 16min