William Warder Cadbury (Chinese name: 嘉惠霖; 1877 – October 15, 1959) was an American physician, professor, researcher, author, and medical missionary. After graduating from University of Pennsylvania's Medical School, he traveled to Canton (Guangzhou), China, where he eventually became the most well known internal medicine doctor in the region during the time period of the Republic of China. At Canton Hospital, he served as a doctor, professor, writer, and eventually Superintendent multiple times. In his 40 years working in Canton (1909-1949), he put forward relentless efforts to improve the Canton Hospital and nearby areas in Canton, bettering the health of many thousands of Canton people In 1935, he published a detailed book on the history of the hospital, called At the Point of a Lancet.