The emphasis on "root cause" problem solving is fundamental to the philosophies of JIT, lean manufacturing, continuous improvement, the Toyota production system, and TQM. It means solving problems at the root rather than at the superficial or immediately obvious levels. But how do you get to the root cause? In the following sections two techniques are examined. But first, we should look at the whole concept of root cause analysis.

In a thoughtful article Finlow-Bates concludes that there are no ultimate root causes. Rather, root causes are dependent upon the problem owner; there can be more than one potential root cause and that the final choice of root cause cannot be made until the economics of possible solutions have been considered. He illustrates the point by the example of a delivery failure. The root cause for the customer is that the parcel is late. The root case for the delivery company is that the problem delivery failure was due to the van not starting which can be traced to the root cause of a leaking underground tank. For the tank supplier the root cause was a failure in the solder. For the solder supplier the root cause was ?. Each person along the chain is not interested in the problems of lower echelons. Each of these causes represents a failure in control or in communication. The real issue is therefore not what is the root cause, but how can be problem be (temporarily?) solved most economically and effectively to prevent recurrence.

Finlow-Bates suggests following six steps:

• What is the unwanted effect? (Finlow-Bates suggests two words; subject and deviation, for example parcels late)
• What is the direct physical cause?
• Follow the direct physical line of the cause. For example, parcels late, van won't start, etc. This establishes the "staircase"
• Ask who owns the problem at each stage.
• Identify where should one intervene in the staircase to effect a long-term solutions.
• Identify the most cost-effective of the solutions.