War demands a large amount of material supply. During times of war, extractive, agricultural, and manufacturing companies typically attend to producing and supplying materials for the war effort rather than for civil consumption. Enemies may interfere with normal supply lines, further complicating the delivery of needed resources. As a consequence, shortages in the material supply, often termed commodity shortages, may emerge. To address such commodity shortages, rationing—that is, limiting the supply or distribution of particular commodities (e.g., water, food, fuel, and clothes) or their properties (e.g., size, quality, and variety) to various social groups—may be instituted voluntarily or through governmental management. This entry reviews rationing and commodity shortages throughout history.