Because key building blocks of lean production have emerged from concepts native to industrial engineering, it is reasonable to assert that we industrial engineers (IEs) have served as primary caretakers of the lean production/lean management movement. For all that, however, a few concepts once widely admired and practiced by IEs (e.g., process layouts; economic order quantities) have been shown to be at odds with the dictates of lean and its closely linked predecessor, just-in-time production. But IEs adapt, casting off what are found to be dubious and readily adopting such later-arriving essentials of lean as cells and kanban.