The primary sources for this text come from a collection of medieval manuscripts discovered in 1900 in a walled-up room in the Buddhist cave-shrines of Dunhuang, Gansu Province, west China. Dunhuang was formerly an important Silk Road town, and formed the base of one of the first garrisons to be established during the Han period to secure the safe passage of soldiers, officials and traders between east and west. While the majority of the manuscripts stored in the cave are copies of Buddhist scriptural texts, there are also thousands of non-Buddhist texts, both religious and secular. The presence among these of some one hundred medical texts suggests that the Dunhuang prefectural school was a center for copying and transmitting medical writings. In the collection we find the earliest handwritten copies of well-known classical medical treatises, together with hitherto unknown medical works, including illustrations and charts, texts related to religious and popular healing traditions and extensive portions of texts previously known only through brief quotations in later works. This is the first book to discuss this fascinating material in a western language in the century since the Dunhuang library was discovered.