Swimlane diagram

A swimlane diagram is a flowchart with an extra dimension: each lane is a person, team or system, and a step sits in the lane of whoever performs it. Handoffs become visible, and handoffs are where processes break.

It is the diagram to draw when the argument is about ownership rather than sequence.


#When to reach for one

  • Cross-team processes where every delay happens at a boundary.

  • Onboarding or procurement flows that touch four departments.

  • Any process where somebody has said "I thought they were doing that".


#How to draw it in Capable

Route

Use when

draw.io

Full control of lane widths, colours and shapes; the usual choice.

ActDiag

You want lanes generated from text and laid out automatically.


#A worked example

An expense claim, generated from text:

Swimlane diagram

The source, which you can paste into a new diagram and edit:

actdiag {
  claim -> manager -> finance -> paid;
  lane employee {
    claim [label = "Submit claim"];
  }
  lane manager {
    manager [label = "Approve"];
  }
  lane finance {
    finance [label = "Check receipts"];
    paid [label = "Pay"];
  }
}

#A few things that catch people out

  • More than five lanes and the diagram stops being readable. Group roles instead.

  • A lane with one box in it is usually a role that does not need its own lane.

  • Keep time flowing one way, left to right or top to bottom, never both.



Draw the unhappy path too.