Working at Toyota Taiichi Ohno developed kanban to create a just-in-time flow and reduce the inventory. The system takes its name from the signal cards that track production within a factory.
While kanban was introduced by Taiichi Ohno in the manufacturing industry, it is David J. Anderson who was the first to apply the concept to IT, Software development and knowledge work in general in the year 2004. David built on the works by Taiichi Ohno, Eli Goldratt, Edward Demmings, Peter Drucker and others to define the Kanban Method. His first book on Kanban – “Kanban: Successfully Evolutionary Change for your Technology Business”, published in 2010, is the definition of the Kanban Method for knowledge work.
Delivering work in a quick and effective way could be a challenge. Kanban is a method for designing and effectively managing knowledge work without overburdening staff, reducing the time to market and improving staff engagement.
Kanban manages work by balancing demands with available capacity, through limiting the work in progress and by improving the handling of system-level bottlenecks.
Kanban system is one that controls and limits the amount of the work in progress to improve the flow of work. A kanban systems uses kanbans that are tokens that represent work and create the pull signal that releases more work to enter the system.
The number of the available kanbans (tokens) is limited which creates a kanban system.
A kanban board is one the visualises the process and the work item. In knowledge work we can’t see the work and have tokens (Kanban cards) that represent the work and the board visualises the process, that is the work flow and where each work item is within the work flow.
The number of available cards is limited to create a kanban system.
The columns on a kanban board show the key steps in the workflow.
This is the fundamental step where the key knowledge discovery steps as currently practised are visualised and the flow of work is mapped. Most kanban systems will have more than one type of work flow across them two common ways to show different types of work are colour or swim lanes.
Different types of work are visualized using different colors on the board and we can get a sense of the blend of work by the colors.
Swim lanes achieve the same result by having dedicated lanes per type of work.
Kanban system is one where the amount work in progress (WIP) is limited, limiting WIP is fundamental in creating a pull-based system of work.
By limiting WIP, we minimize the opportunity for multi-tasking and create the conditions for the team member to focus on finishing the work at hand before starting something new.
Kanban systems are designed to improve flow, managing and improving flow is the key action that is required. A Kanban system helps manage flow by visualizing the workflow and where the work item is within the workflow. The flow of work is managed by managing the amount of work that piles up (this is a signal that the arrival rate at the stage is greater that the processing rate). As the number of work items grow so does the lead time. The WIP limits create a buffer of appropriate size that smooth the flow while at the same time ensuring that the overall lead time remains within acceptable customer expectation.
Policy constraint are a key cause of long lead times and because they are introduced by the people within the system we should be able to address the policy constraints that are impeding flow. Policies also make what is required to be done to a given work item at each step of the workflow enabling built-in quality. Examples of explicit policies include the Definition of Done, when and how WIP limits are adjusted. Policies can apply to the system as a whole (the board), swim lanes, columns and combinations of the above.
Reducing the time to feedback and increasing the number of feedback loops is the key to any good system design.
Evolve Experimentally (using the scientific method)
Improve collaboratively to minimize the chances of local optimization, evolve experimentally using scientific method through hypothesis, experiments and observation.
95% of the performance is the result of how the system of work is designed and managed. Dr Edward Deming
Kanban method enables you to design and act your system of work and significantly improve the results.
Kanban flow measures and the use of probabilistic forecasting enable the organisation to have high confidence in their deliveries and enable the organisation to make promises that they can keep.
The lead time measure allows us to answer when can I expect delivery of this feature?
As you can see from the Lead Time chart we can answer this question with 90th percentile confidence that the feature is likely to complete in 15.4 days or less.
My project has more than one feature, how do we forecast the likely completion date?
Start with some basic information.
How many features do you have in your project?
What is your current delivery rate, per week?
We can use the delivery rate to forecast a likely completion date we can use the 50th and 90th percentile delivery rate to forecast the likely range of delivery dates.
Here’s a basic example:
Number of weeks to complete
How many features do we need to deliver?
|What is the weekly delivery rate which the team can hit 90% of the time?||4.4||23|
|What is the weekly delivery rate which the team can hit 85% of the time?||5.8||17|
What is the weekly delivery rate which the team can hit 80% of the time?
What is the weekly delivery rate which the team can hit 50% of the time?
We can deliver this initiative that has 100 features between 10 to 23 weeks with the confidence of 50th to 95th percentile.
Companies large and small use Kanban and report benefits of Kanban. Value Glide has enabled organisations in finance, insurance, online gaming, media and government agencies to benefit from kanban.