Description:A transnational language, Bisu is spoken in the border areas of China, Thailand, Myanmar, and Laos. It was first described in Thailand in the 1960s, and is an important member of the Bisoid branch of the Burmese-Yipho group within the Tibeto-Burman language family. Other members of this branch include Phunoi, Sangkong, Mpi, and Pyen. This is an English translation of a linguistic description of the Bisu spoken in Yunnan Province in southwestern China. The original Chinese text was written by Xu Shixuan of the Institute of Nationality Studies of the Chinese Academy of Social Sciences, as part of the series Newly-Discovered Languages in China. The volume analyses and describes Bisu in terms of its structure, its relationship to other languages in the same family, and its socio-cultural background, presenting a comprehensive and systematic overview of the language. There are extensive discussions of the origins and forms of loan words in Bisu, a detailed description of its dialects, as well as numerous charts of Burmese-Yipho cognates. The two appendices include a lexicon of over 2,000 words and three Bisu odes. This thorough description of one of the lesser-known minority languages of China provides an excellent record of a language whose speaker numbers are declining. In addition, the distinctive features of Bisu and the effects of contact with other languages such as Thai and Dai can offer new perspectives in the investigation of Tibeto-Burman languages.