Core Concept
Kanban is a flow-based method for managing work. There are no fixed sprints, no roles, and no prescribed ceremonies — work flows continuously from backlog to done, limited by the team's real capacity.
Originally a Toyota manufacturing system. Adapted for knowledge work by David J. Anderson (~2007).
The Board
A Kanban board makes work visible. Columns represent workflow states:
Backlog → Ready → In Progress → Review → Done
Each card is a work item. Teams customize columns to match their actual process (e.g. add "Blocked", "Waiting for QA", "Deployed").
WIP Limits
The key practice that separates Kanban from a simple task board.
- WIP (Work In Progress) limit: maximum number of cards allowed in a column at one time
- Forces the team to finish before starting new work
- Exposes bottlenecks — if a column is always full, the step after it is too slow
- "Stop starting, start finishing"
Example: In Progress column capped at 3 → no new cards pulled until one moves to Review.
Key Metrics
| Metric | Definition | Why it matters |
|---|---|---|
| Cycle time | Time from "started" to "done" | Measures delivery speed per item |
| Lead time | Time from "requested" to "done" | What the customer experiences |
| Throughput | Items completed per time period | Team capacity signal |
| Flow efficiency | Active time / total lead time | Reveals idle/wait time |
Goal: reduce cycle time and increase flow efficiency over time.
Kanban vs Scrum
Quick rule of thumb:
- Kanban when work arrives unpredictably and continuous delivery matters more than batched releases.
- Scrum when work is feature-shaped, stakeholders need rhythm, and the team can commit to a Sprint Goal.
Full comparison, decision guide, and Scrumban hybrid: scrum-vs-kanban.md.
When to Use Kanban
- Support/ops teams where work arrives unpredictably
- Maintenance work with no fixed sprint goal
- Teams transitioning from ad-hoc chaos to a process
- When Scrum's ceremony overhead outweighs its benefit
- Mixed workload: new features + bugs + hotfixes together
Scrum when you have dedicated feature teams building toward sprint goals.
Kanban when work is interrupt-driven or continuous.
Kanban Principles (Anderson's original four)
- Start with what you do now
- Agree to pursue incremental, evolutionary change
- Respect current processes, roles, and responsibilities
- Encourage acts of leadership at all levels