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CIRAS - TOC - Thinking Processes

Prerequisite Tree (PRT)

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When using the Thinking Processes, the third of 3 questions you should ask  is:

  • "How to cause the change?"

The wording here is very important! Note that it does not ask 'how to change things?' The emphasis is on causing the change to happen. Since people tend to be less resistant to changes that they helped design, the key is to involve the people who will have to execute the changes in a meaningful way.

This portion of the Thinking Process is perhaps its greatest strength—that which sets it apart from many other processes of continuous improvement. In my experience, once a group/team/manager determines what to change to, the implementation "team" too often goes into full operation: set dates, take names, and don't let anything get in the way. Not so with the Thinking Process. You see, at this point all we have are a clear picture of the core problem that is causing our current pain (from the Current Reality Tree), the breakthrough idea that can significantly improve our condition (from the Evaporating Cloud) and assurance that this idea will indeed change the undesirable effects we are currently experiencing into desirable effects in the future (from the Future Reality Tree). We have not considered at all how to get from our undesirable current reality to our desired future reality.

The next step is to work closely with the people who are going to be asked to change. Their involvement is absolutely vital to the long term success of the implementation. As they view the proposed change, the "injection" and rosy "future reality" that accompanies it, they will tend to be resistant. Remember that the core problem has probably existed for some time, and that there is a significant conflict underlying the current behavior. Thus, the proposed injection will usually be counter to the culture of the organization (or the department or sub-group of the organization).

People will usually look at the proposed solution and say, "Yes, I see where your idea might work, but...." One way these people complete this sentence is by identifying  obstacles that seem to make the chances of successfully implementing the idea very small. For example:

  • Yes, your solution sounds good, but it requires that marketing and engineering must communicate closely with each other, and in our company they aren't even on speaking terms.
  • Yes, your idea may work, but before we could implement it we would have to train everybody in the organization and we don't have any money in the budget for that.
  • Sounds great, but The Big Boss will have to give her approval first, and you can forget that!

These obstacles are pro-actively sought, and the person who originally pointed out the obstacle is asked to identify the conditions that would be necessary to overcome it. By helping the originator to solve the problem, not only do you develop effective solutions, but buy-in from the participants is very high. The mapping tool that is used to logically show what is necessary to overcome these obstacles is called the "Prerequisite Tree."

There is another way that people can complete the sentence, "Yes, but...." It is by identifying unintended negative consequences; these are discussed in the section on Negative Branches.

"Give me a lever long enough and a place to stand, and I will move the world."