Showing your Kanban!

I just stumbled across this story on the origins of kanban.
Fredharriman.com tells us:

In once incidence remembered by Chihiro Nakao, Mr. Ohno caught someone he knew was about to pull his materials too soon and thundered: "Who are you and where did you come from?! What makes you think you have any right to this material?
Show me your kanban!!"

This illustrates some of what a kanban is not - it isn't a purchase order, it isn't a fax, and it isn't a taped or marked location. All of these can be part of a kanban, but a kanban is simply "a visual control that signals an upstream operation to deliver what is needed." (taken from Ralph Bernstein).

It is the "authority" created by need to "pull" an item downstream from an upstream operator.


Delving into JIT is a difficult process - one that takes time, effort, and
committment. We all know that going lean yields great rewards, but in
the midst of the difficult process of "gettling lean," it's nice to be
reassured that even the originators had trouble from time to time.