Premodern literature in the Islamicate world presents a wide array of texts dealing with the organisation of knowledge, typically in the form of classifications of the sciences. The present survey traces this intellectual tradition from Arabic, Persian, and Turkish sources. Taken together, the examples provided here to illustrate the history of science classification over about one millennium (from 800 to 1800) offer a panorama of exceptional richness and variety, testifying to an astonishing degree of creativity over the longue durée.