Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for managing orders. The methods include actions of tracking performance of a fulfillment center in fulfilling orders for items at the fulfillment center, storing historical preparation information that describes historical performance of the fulfillment center, and receiving an order for an item to be fulfilled by the fulfillment center for a fulfillment time. Additional actions include obtaining a portion of the stored historical preparation information that is relevant to fulfillment of the item by the fulfillment time, obtaining current order information that describes other orders to be fulfilled at the fulfillment center, determining whether the fulfillment center can fulfill the order by the fulfillment time based at least on the portion of the stored historical preparation information and the current order information, and providing an indication to a user device that the order cannot be fulfilled.