Kanban
Kanban is an occurrence driven framework that is widely applied in manufacturing industry. The ideas of Kanban have been adapted for use in software engineering. In contrast to cadence-based frameworks such as Scrum, Kanban focuses on the efficient continuous flow of work. To enable continuous flow, transparency of process and full visibility of all the work are two critical focuses for the team.
Unlike most other frameworks, there is no process implied by Kanban. This represents a challenge to inexperienced teams who think of adopting Kanban. Instead of a framework defined process, there are principles and practices that teams are expected to put into effect for themselves. By applying the principles and practices, the team will create a system of work for itself.
The starting point is to visualise the process. In other words, the team is responsible for defining what its process is. Flow through the visualised process is enabled by limiting work in progress to ensure that the team operates a pull system of work. We seek to further manage flow of work to ensure a high and sustainable rate of flow. Explicit policies are associated with each stage of the process helping the team to understand when a backlog item has completed a stage. Feedback loops are included in the process so that occurrences can be detected, understood, and resolved. The team reviews its performance so that it can collaboratively and empirically improve the way it works - resulting in changes to the process, work in progress limits, flow management, policies, and feedback loops.
Implementing these six practices is no simple task. The Kanban principles guide teams on how to effect the change from current ways of working into a full Kanban-based system of work. To be successful, Kanban requires a rigorous adherence to a quantitative understanding of process performance and improvement.
Useful Sources
Kanbanize - A great source of information about Kanban (the company sells a workflow tool to support teams using Kanban). The linked page is the introduction to a fairly comprehensive Kanban tutorial.
Specific Practices
Stop the Line is a practice in Kanban. Whenever a defect is detected downstream of the point where it should have been eliminated, the line is stopped. The team take time to identify and explore the reasons for the escape of the defect. They decide what action to take to prevent defects of the same type escaping in the future. Best practice also uses Stop the Line to identify and reinforce modified practice that brings performance benefits to the work of the team.