Where does the kanban system come from?
Kanban is the Japanese word for a sign or card. It was developed at Toyota as part of the Toyota Production System, where a card travelling with parts told the upstream process what to make and when. Teams later adapted the same pull logic to knowledge work, so "kanban" now covers both card loops and task boards.
How does a kanban system work?
- A downstream step uses something up, such as a bin of parts or a finished task.
- A signal goes upstream: a card, an empty container or a free slot on the board.
- The upstream step makes or does only that amount, and nothing without a signal.
- The signal travels with the work until the next step consumes it, then returns to start the loop again.
The number of cards or slots in circulation sets the limit on work in progress, so the system controls itself instead of relying on forecasts.
What are the rules of a kanban system?
- Never pass on a defect.
- The downstream process pulls only what it needs.
- The upstream process produces only what was pulled.
- Smooth the load so demand does not swing between peaks and gaps.
- Reduce the number of cards gradually to expose problems.
What types of kanban system are there?
| Type | Signal | Typical use |
|---|---|---|
| Production kanban | Card authorising a process to make a set quantity | Cells and lines making repeat items |
| Withdrawal (move) kanban | Card authorising parts to be moved from stock | Supplying a line from a supermarket |
| Supplier kanban | Card or container returned to a supplier | Replenishing bought-in parts |
| Two-bin system | Empty bin | Low-cost fasteners and consumables |
| Kanban board | Cards on columns with WIP limits | Actions, jobs, projects |
Kanban system versus kanban board
The board is one way to run the system. A board with cards and column limits is a kanban system for tasks; a card-and-container loop is a kanban system for materials. Both limit work in progress and make bottlenecks visible. See what is a kanban board for the board layout in detail.
How do you set up a kanban system?
- Choose one flow with steady, repeating demand.
- Map the steps and where work waits.
- Decide the signal: card, bin or board column.
- Set a generous first limit from lead time and demand, then lower it step by step.
- Review daily and fix the cause when signals stall.