Work in Process

Work In Process (WIP) is a measure of the quantity of goods at various stages of completion between raw materials and finished goods throughout a production facility. WIP inventory buildup is a key indicator of waste as it is counter to the philosophy of single piece flow and just-in-time production. This doesn’t mean all Work In Process is evil. Sometimes WIP is necessary for line balancing and for places where some batch production is necessary. All inventory in the diagram below is considered WIP.