Kanban

Kanban uses visualization and pull-based work management via a Kanban board of intangible work items. Intangible work items are visualized to present all participants with a view of the progress of individual items, and the process from task definition to customer delivery. Team members "pull" work as they have capacity, rather than work being "pushed" into the process when requested.

Origins

‘Kanban’ as a concept was popularized by Taiichi Ohno (former Toyota vice president) who took inspiration from how supermarkets stock their shelves and promoted the idea of Just-in-Time manufacturing in Japanese manufacturer Toyota – using kanban cards as a signal between two dependent processes to facilitate smoother – and just in time – flow of parts between them.

Etymology

The word ‘kanban’ has its origin in both hiragana (Japanese language) and Kanji (Chinese language). In hiragana, it means a ‘signal card’ while is kanji it means a ‘sign’ or ‘large visual board’.

Kanban Board

The Kanban board is an important aspect of Kanban since it allows a greater understanding of both the work and the workflow. It also advocates limiting work in progress, which as well as reducing waste due to multitasking and context switching, exposes operational problems and stimulates collaboration to continuously improve the system.

It is used to visualize the flow of work. It moves work items in process as they move around the board. Its movement corresponds with a knowledge work or manufacturing process.

The most common way to visualize your workflow is to use card walls with cards and columns. Each column on the wall represents steps in your workflow. The board has at least three sections: "backlog", "work in progress" and "completed work". More complex Kanban boards can be created, changing the sections to "in progress", "tested", "accepted", "blocking" and so on according to the needs of users of the organization.

Kanban Method

The definition of Kanban has undergone its own evolution and elaboration over the last years.

‘Kanban Method’ is a term first adopted in 2005 by David J Anderson who evolved the kanban concept into a management method to improve service delivery and evolve the business to be ‘fit for purpose’. He combined elements of the work of W Edwards Deming, Eli Goldratt, Peter Drucker, and Taiichi Ohno. David Anderson’s published a post called The Principles & General Practices of The Kanban Method^[1].

Today, Kanban is considered as an agile management method for managing and improving service delivery (in both software/ IT and non-IT contexts) in a gradual, evolutionary manner, kanban is a tool.

Over several years, Anderson distilled the method into a set of principles and practices. These were evolved in collaboration with the wider Kanban community to create the Kanban Method as we know it today.

Principles

The 3 fundamental guiding principles of the Kanban Method are:

1. Start with what you have now – that is your current process.
2. Agree to pursue an evolutionary approach to change and improvement
3. Respect the current roles and responsibilities of the team/ organization.

The six key practices outlined in the Kanban Method include:

1. Visualize the workflow
Break down the flow of work from the moment you start it to when it's finished into distinctive steps and draw a column for each. The most common way to visualize your workflow is to use the Kanban board. Each task will move from left to right until it's done and leaves the workflow.

By creating a visual model of your work and workflow, you can observe the flow of work moving through your Kanban system. Making the work visible—along with blockers, bottlenecks and queues—instantly leads to increased communication and collaboration.

2. Limit work-in-progress (WIP)
Limiting WIP is the cornerstone of Kanban. Limiting work-in-progress implies that a pull system is implemented. Put limits on columns in which work is being performed. The critical elements are that work-in-progress at each state in the workflow is limited and that new work is “pulled” into the next step when there is available capacity within the local WIP limit.

By limiting how much unfinished work is in process, you can reduce the time it takes an item to travel through the Kanban system. You can also avoid problems caused by task switching and reduce the need to constantly re-prioritize items.

3. Measure and Manage flow
It is done by looking at how value is currently flowing through the system, getting leading indicators of future problems by analyzing problem areas in which value flow is stalled and defining and then implementing changes.

One of the best tools to measure Kanban performance is Cumulative Flow Chart. Each day, for each column, mark how many tasks are in it or somewhere further down the workflow. This will produce a mountain-like looking chart, which gives insight into the process, shows past performance and allows to predict future results.

4. Make process policies explicit
The process needs to be defined, published and socialized.
5. Implement feedback loops
This practice was added in the Sep 2014 update to the list on The Principles & General Practices of The Kanban Method. In scrum, for example, Feedback loops can be implemented as daily standup, improvement kata (daily improvement activity, removing impediments), operational review (using analysis of data) or other techniques.
6. Improve collaboratively, evolve experimentally
Once the Kanban system is in place, it becomes the cornerstone for a culture of continuous improvement. Teams measure their effectiveness by tracking flow, quality, throughput, lead times and more. A scientific approach is used to implement continuous, incremental and evolutionary changes.

Applications

Kanban works on the target process, whether a software or IT process or a general business process, and helps to smooth the flow of work to maximize “throughput” and achieve high product quality. Kanban helps to make changes and improve a process (Kaizen). As such, Kanban often results in a new process that is worked out by the team or the organization itself in a collaborative and gradual manner. In the context of software and IT, Kanban helps teams to deliver software and services more smoothly, more frequently and at an optimized flow and throughput levels. A team that is currently using the Scrum method will be able to change its process to potentially move away from a batch/ time-boxed delivery method to a more continuous delivery model.

References

Agile Project Management with Kanban (Developer Best Practices). Eric Brechner. Microsoft Press, March 26, 2015.

Notes

1. ^ Anderson, D. (2010c, 10 Dec; Updated Sep 2014). The Principles & General Practices of The Kanban Method.