Li Cheng, style name Yuji, a physician during the Southern Song dynasty, was a native of Gushu (in present-day Anhui Province). Although he served as a secretary in the cabinet, Li was mainly known for his medical knowledge. He rearranged the work of the Han dynasty physician Zhang Zhongjing (active 168−96), entitled Shang han za bing lun (Treatise on cold pathogens and miscellaneous diseases). Zhang’s work was later organized by Jin and Song dynasty physicians into two books, one of them with the title of Shang han lun (On cold damage). Li Cheng’s compilation differs in listing first the prescriptions, then the classified categories. He named his work Shang han yao zhi (Essentials for cold damage diseases and prescriptions). Li Cheng’s other works were Shang han zhi fa cuo yao (Summaries of treatments of cold damage disorders) and Xiao er bao sheng fang (Prescriptions for infant care), but neither of them has survived. This work, Shang han yao zhi yao fang (Essentials for cold damage disorders and prescriptions), in two juan, was printed in the seventh year of Qiandao of the Southern Song (1171). Juan one contains prescriptions drawn from a Northern Song edition of Shang han lun, issued by the Bureau for Revision of Medical Classics, from which Li selected and recorded more than 100 prescriptions. Juan two contains the essentials for treating cold disorders, with 172 entries selected from the Shang han lun. Also included are ten entries of “do’s and don’ts.” The work is of great practical use, and with the simple text of the Northern Song edition, it provides a significant resource for the study of the development and dissemination of Shang han lun and of its revised editions. Just a year prior to the printing of this work, another great work, Hong shi ji yan fang (Hong's collection of effective prescriptions), was published and was in the private collection of Huang Pilie (1763−1825). This copy of Li Cheng’s work was owned by the bibliophile Pan Zongzhou (1867−1939) in his private library called Baolitang. In 1950 the descendants of Pan donated the book to the National Library of China.