In the FRT Future Reality Tree we created "Injections," those conditions that would have to be in place in order for the symptoms to be eliminated. This was the tool we used to build the "To What to change" plan.
In the PRT Prerequisite Tree we identified the major obstacles to any challenging Injections, and mapped out a path through, around and over those obstacles. We might even have assigned names to the stages of that PRT, and timelines.
But now we're still left with the need for an action plan to follow that path and put the Injections in place; and that's where the Transition Tree, or TT, comes into play.
The Transition Tree is a cause-effect planning tool that nails down the action plan
Another Effect-Cause-Effect diagram, the Transition Tree is a deceptively simple tool used to develop a detailed action plan of precisely what must happen, in time-sequenced, cause-effect detail, in order to have a high degree of assurance that a desired outcome will be achieved in reality.
Again, this is not confined to use in a Theory of Constraints environment.
The standard use of the Tool was to help develop an action plan with a high degree of likelihood of achieving it's objective; and initially, the objective would be one of the Injections in a Future Reality Tree.
But I've used a Transition Tree that sequenced a 10-day workshop (the "Jonah Course" as it was called) so that every stepping-stone to understanding would be understood before the next level was attempted. Extraordinarily powerful.
I will also use this when I've a 5-minute (but important) telephone call to make, one where I have a clear outcome in mind and want to be sure I have a high degree of assurance of achieving it.
I've seen the tool used effectively (described in a colleague's book) to lay-out a procedure for dealing with "incidents" in a company, for example, where it's important that the supervisor responsible not only performs the appropriate actions but clearly understands why he or she is performing them, and what the shape of the outcome is expected to be.
The Transition Tree is simple, powerful tool to ensure that not only the "What" but the "Why" of a series of actions is clear to everyone associated with a plan.