The history and constitution of Chinese ink is reviewed briefly as part of a special issue on Writing Systems. There are a considerable number of historical accounts of ink from China, going back to the 5th or 6th century. The essential constituents are carbon, in the form of soot or lampblack, and animal glue, but fine ink requires great care in both selection and mixing. Many other things were added from time to time, especially in earlier periods. There has long been a strong appreciation of ink quality in China, Japan, and Korea.