Project Management guide · Scheduling and time
Swimlane Diagram: What It Is, Examples and How to Make One
A swimlane diagram is a flowchart divided into horizontal or vertical lanes, one for each person, team or system involved in a process. Each step sits in the lane of whoever performs it, so you can see at a glance who does what and where work is handed over.
Key takeaways
- A swimlane diagram shows process steps in lanes for each person, team or system.
- Arrows crossing lanes show handoffs, which are common sources of delay.
- Map the current process with the people who do it before improving it.
- Keep lanes few and steps at a consistent level of detail.
When to use a swimlane diagram
- Mapping a process that crosses several teams, such as onboarding or change approval.
- Clarifying roles alongside a RACI matrix.
- Finding delays, duplicate work and unnecessary handoffs.
- Designing a new workflow for a project deliverable.
- Showing parallel work streams on a project plan; some Gantt charts and Kanban boards use lanes in a similar way.
Common symbols
| Symbol | Meaning |
|---|---|
| Rounded rectangle or oval | Start or end |
| Rectangle | A step or activity |
| Diamond | A decision with yes/no branches |
| Arrow | Flow of work or information |
| Document shape | A document produced or used |
| Lane | The person, team or system responsible |
How to make a swimlane diagram
- Choose one process with a clear start and end.
- List the people, teams or systems involved and create a lane for each.
- Walk through the process with the people who do it, writing each step in the right lane.
- Add decision points and the paths that follow them.
- Connect the steps with arrows; every arrow crossing a lane line is a handoff.
- Review with each lane owner, then look for delays, loops and unnecessary handoffs.
- Optionally add durations to each step to estimate the process cycle time.
Example: project change request
| Lane | Steps |
|---|---|
| Requester | 1. Submit change request |
| Project manager | 2. Log request -> 3. Assess impact on scope, schedule and cost |
| Change board | 4. Decision: approve? Yes -> step 5. No -> step 6 |
| Project manager | 5. Update plan and baseline / 6. Inform requester of rejection |
| Team | 7. Carry out the approved change |
The diagram shows four handoffs. If the change board meets fortnightly, step 4 can add up to 10 working days of waiting, which is the obvious improvement target. See change control.
Tips
- Keep to five to seven lanes; more becomes hard to read.
- Use the same level of detail throughout.
- Name steps with a verb and noun, such as "Approve invoice".
- Map the process as it really works today before designing the improved version.
- Many project management tools and diagramming tools include swimlane templates.
Free templates for this topic
Frequently asked questions
What is a swimlane diagram?
A flowchart split into lanes, one per person, team or system, showing who carries out each step in a process.
Why is it called a swimlane diagram?
The lanes look like the lanes in a swimming pool, with each participant staying in their own lane.
What is another name for a swimlane diagram?
It is also called a cross-functional flowchart, a Rummler-Brache diagram or a deployment flowchart.
When should I use a swimlane diagram?
When a process involves several people or teams and you need to show responsibilities and handoffs.
What is the difference between a flowchart and a swimlane diagram?
A standard flowchart shows steps; a swimlane diagram also shows who does each step.
Can swimlanes be vertical?
Yes. Lanes can run horizontally or vertically; choose whichever fits the page better.
How many lanes should a swimlane diagram have?
As few as needed, typically no more than five to seven for readability.
What are swimlanes in a Kanban board?
Horizontal rows that separate types of work or teams on the same board; see Kanban swimlanes.
What are swimlanes in a Gantt chart?
Groupings of tasks by team, workstream or owner, used to show parallel streams of work.
What tool can I use to make a swimlane diagram?
General diagramming tools and many project management software products offer swimlane templates.