Optimizing flow requires defining what flow means in a given context. The explicit shared understanding of flow among Kanban system members within their context is called a Definition of Workflow (DoW). DoW is a fundamental concept of Kanban. All other elements of this guide depend heavily on how workflow is defined.
At minimum, members must create their DoW using all of the following elements:
- A definition of the individual units of value that are moving through the workflow. These units of value are referred to as work items (or items).
- A definition for when work items are started and finished within the workflow. Your workflow may have more than one started or finished points depending on the work item.
- One or more defined states that the work items flow through from started to finished. Any work items between a started point and a finished point are considered work in progress (WIP).
- A definition of how WIP will be controlled from started to finished.
- Explicit policies about how work items can flow through each state from started to finished.
- A service level expectation (SLE), which is a forecast of how long it should take a work item to flow from started to finished.
Kanban system members often require additional DoW elements such as values, principles, and working agreements depending on the team’s circumstances. The options vary, and there are resources beyond this guide that can help with deciding which ones to incorporate.
The visualization of the DoW is called a Kanban board. Making at least the minimum elements of DoW transparent on the Kanban board is essential to processing knowledge that informs optimal workflow operation and facilitates continuous process improvement.
There are no specific guidelines for how a visualization should look as long as it encompasses the shared understanding of how value gets delivered. Consideration should be given to all aspects of the DoW (e.g., work items, policies) along with any other context-specific factors that may affect how the process operates. Kanban system members are limited only by their imagination regarding how they make flow transparent.