A five-year survey will be conducted of the biodiversity of the Gaoligongshan region of western Yunnan Province, People's Republic of China. The Gaoligongshan region, which extends from the eastern Himalayas to southern Yunnan Province, is recognized by global conservation agencies as one of the "hottest" of biodiversity hotspots worldwide. At the heart of this region lies the Gaoligongshan, a spectacular high ridge of mountains running some 600 km from north to south near the border between southwestern China and northeastern Myanmar (Burma). Unlike much of the surrounding area, the forests of the Gaoligongshan have remained largely intact because of their remote location. The survey will be very broad taxonomically and include the following groups: bryophytes and vascular plants, diatoms, arthropods, and vertebrates. The foundation for this project consists of a three-way collaboration between the California Academy of Sciences (CAS), the Kunming Institute of Botany, and the Kunming Institute of Zoology. To provide sufficient scientific expertise for our endeavor, the three primary institutions will collaborate with a number of other institutions that maintain vigorous research programs on the Chinese biota: the Royal Botanic Garden Edinburgh, the Institute of Zoology in Beijing, Hunan Normal University, the Missouri Botanical Garden, Harvard University, and the United States National Herbarium. A large number of experts have been recruited worldwide to aid in the identification of specimens belonging to the most species-rich taxonomic groups (plants and arthropods). The CAS will collaborate directly with the Yunnan Cultural Relics and Archaeology Institute in a survey of quaternary cave deposits. This will complement the neontological survey by providing a picture of how the Gaoligongshan's vertebrate fauna has changed since the mid-Holocene with the advent of intensive agriculture. The project includes a major training component for Chinese graduate students, postgraduates, and employees at nature reserves. The information generated from this project will provide the basic knowledge necessary for sound management and conservation decisions affecting the Gaoligongshan ecosystem. The collections resulting from the project will be used by members of the project team in various scientific endeavors, from the publication of monographs to molecular phylogenetic studies. The data also will be used as the basis for more specific studies of evolutionary patterns and processes, such as tests of biogeographic models of the northern hemisphere, biodiversity and environmental patterns through time and space, and the utility of the hotspot concept in predicting the diversity of poorly inventoried groups.