Kanban is a method for managing knowledge work with an emphasis on just-in-time delivery while not overloading the team members. In this approach, the process, from definition of a task to its delivery to the customer, is displayed for participants to see. Team members pull work from a queue.
David Anderson was among the first to formulate the Kanban Method for application to IT and software development in his 2010 book Kanban. A notable earlier contribution came from Corey Ladas, whose 2009 book Scrumban was the first to suggest that Kanban was a superior alternative to Scrum for software development. Corey's book saw Scrumban as the transition from the starting point of Scrum to the destination of Kanban.
More recently, in 2013, Joseph Hurtado introduced Open Kanban, an open source, minimal, Agile and Lean method that is designed to be extended and customized. In addition, the Kanban Ace was written as an extension of Open Kanban particularly suited to software development.
Formulated by David Anderson, the Kanban Method is as an approach to incremental, evolutionary process and systems change for organizations. It uses a work-in-progress limited pull system as the core mechanism to expose system operation (or process) problems and stimulate collaboration to continuously improve the system. Visualisation is an important aspect of Kanban as it allows to understand the work and the workflow.
The Kanban Method is rooted in four basic principles:
Start with existing process
The Kanban method does not prescribe a specific set of roles or process steps. The Kanban method starts with existing roles and processes and stimulates continuous, incremental and evolutionary changes to the system. The Kanban method is a change management method.
Agree to pursue incremental, evolutionary change
The organization (or team) must agree that continuous, incremental and evolutionary change is the way to make system improvements and make them stick. Sweeping changes may seem more effective but have a higher failure rate due to resistance and fear in the organization. The Kanban method encourages continuous small incremental and evolutionary changes to your current system.
Respect the current process, roles, responsibilities and titles
It is likely that the organization currently has some elements that work acceptably and are worth preserving. The Kanban method seeks to drive out fear in order to facilitate future change. It attempts to eliminate initial fears by agreeing to respect current roles, responsibilities and job titles with the goal of gaining broader support.
Leadership at all levels
Acts of leadership at all levels in the organization, from individual contributors to senior management, are encouraged.
Open Kanban is an open source, Agile and Lean based method to deliver value for knowledge work like information technology, software development, business, product development or personal organization. On the Lean side it is inspired on the work of Taiichi Ohno (Toyota Production System), Eliyahu Goldratt (Theory of Constraints) and Edward Deming. On the Agile side it takes inspiration from the Agile manifesto signers, and in addition contributions from Alan Shalloway's Kanban for Teams, Corey Ladas Scrumban and David Anderson's early Kanban work.
It innovates by making the whole method fully open source and free to improve or modify, under the CC BY license. Open Kanban was written by Joseph Hurtado, and it has been translated by members of the community to French, Italian, Portuguese, Spanish, Russian and Ukrainian.
Open Kanban Agile and Lean heritage is reflected in its core values Respect for people, Courage, Focus on Value, Communication-Collaboration, and a Holistic or Systemic Approach to Change. Those values manifest in 4 key practices:
1. Visualize the workflow.
You cannot improve what you cannot see. Knowledge work needs a way to show progress. Kanban boards are one of the ways to display progress.
2. Lead using a team approach.
Without a team and leadership, nothing of significant value can be created or improved.
3. Reduce the Batch Size of your Efforts or Reduce BASE.
Science and the work from Donald G. Reinertsen  has shown that when the batch unit of work is decreased, more can be accomplished. This principle goes beyond simply Limiting Work in Progress.
4. Learn and improve continuously.
This practice implies reflecting so that one can learn from experience, and it aligns with performing retrospectives and embracing Kaizen. In addition Open Kanban itself is open source and it welcomes contributions or extensions to the method.
While developed for software development and software teams, the Kanban method (as distinct from Kanban) has been applied in other areas of knowledge work. As a visualization and control mechanism, any repeatable and consistent workflow can be tracked, regardless of complexity or subject area. Business functions that have applied Kanban include: