Kanban
Kanban (Japanese for “signboard” or “card”) is a visual signalling system that triggers the replenishment or production of an item when it is consumed, so that supply is pulled to match actual demand rather than pushed in advance. In its classic form, a card (or bin, or now a digital signal) accompanies a batch of parts; when the parts are used, the card is sent back as the signal to make or order more.
Kanban is the practical mechanism that makes just-in-time work: it limits the amount of inventory or work in progress to the number of kanban signals in circulation, preventing overproduction and keeping stock low while ensuring items are replenished just as they run out. Simple and self-regulating, it gives clear visual control of flow and exposes bottlenecks. Originating in manufacturing (the Toyota Production System), kanban is now widely used for inventory and stores replenishment (including two-bin systems) and, in adapted form, for managing workflow in services and software. It is a cornerstone of lean and pull-based supply.
Kanban is the elegant mechanism that turns "make to forecast" into "make to actual use" — a simple visual signal that caps inventory and replenishes exactly as stock runs out. It is what makes JIT and pull-based supply actually function on the floor, and its clarity in exposing flow and bottlenecks is why lean operations everywhere rely on it.
How does kanban work?
A card or signal accompanies a batch of stock; when consumed, the signal triggers replenishment, pulling supply to match demand.
How does kanban relate to JIT?
Kanban is the signalling mechanism that makes just-in-time work, limiting inventory to the signals in circulation.