Dr. T.L. Yates and Mr. J.A. Cook of the University of New Mexico and Dr. S. Anderson of the American Museum of Natural History will continue their survey work on mammalian diversity in Bolivia, by conducting five elevational transects through the Andes Mountains in the Yungas and Valles region between 500 and 3000 M and obtain representative specimens, genetic material, and parasites from all ecological zones. The study is also designed to involve Bolivian students and professionals, thus, providing training in conservation and biodiversity, and to continue to collaborate with and expedite the studies of other workers doing research on South American mammals. Few South American countries are as biologically unknown as Bolivia. This is particularly true of the largely unexplored, biologically diverse regions to be examined in this study. Much of this area has been opened to large scale development and deforestation. Information provided by this study will provide a critical baseline for evaluating the future impact of this development on the biodiversity of the region and will provide an important database for broad scale comparative research. It will also provide important training for Bolivian biologists wishing to continue this type of work in Bolivia.