The vast remote Tibetan steppe, the Chang Tang, is home to a unique assemblage of large mammals, including the Tibetan antelope, gazelle, argali sheep, wild ass, wild yak, wolves and snow leopards. This text is the result of the author's research into the natural history of this little-known eco-system. The plains ungulates are the main focus of the book, especially the Tibetan antelope or chiru , whose migrations define this eco-system much as those of the wildebeest define the Serengeti. Descriptions of mammal numbers and distribution, behaviour and ecology are provided, information which may allow wildlife, grasslands and pastoralists to continue to coexist harmoniously in this region. This project led to the creation of the 130,000-square-mile Chang Tang reserve by the Tibetan government in 1993, and conservation and management efforts continue.