Sürsat was a form of food requisitioning with price controls, used by the Ottoman Empire to provide consumables for its armed forces. It was related to nüzül; sürsat was initially an obligation for the public to provide food and other supplies at a pre-fixed price which was unlikely to be favourable, or might even be merely symbolic. was basically the same obligation, but supposedly at market price. Over time, nüzül, sürsat, and istira were all transformed into extraordinary cash taxes on people living near the route travelled by the army.