Lean can be a very broad term in the process and production management realm.
In practice, it’s anything from a 4-man production team deciding to simplify their process within 1 week, to a corporate overhaul of all processes, positions and procedures, which can take months or years and involve hundreds of people.
But the goal is always the same: making a process leaner - more simple, more predictable and reliable, less wasteful in time, material and effort, and through all this and more - of course - more profitable.
Lean thinking draws heavily from the Toyota Production System and hence associates strongly with Kanban. It’s also closely connected with Six Sigma and with the Agile movement for software development and knowledge-based process management, at least in the alignment of the 2 ideas goals.
This section of the Kanban Guide introduces you to the general ideas driving Lean-based changes and processes, while the Lean Methodology section presents the specific ways in which the thinking is best applied.