The principle of management by exception uses six types of tolerance against which a project can be controlled.
The allocation of tolerances follows the four levels of the project management team as outlined in the diagram and described below:
Sits outside the project but sets the overall requirements and tolerance levels for the project.
The three levels of management within the project (responsible for directing, managing and delivering) will manage and implement within these tolerances and escalate any forecast breaches of project tolerance.
Has overall control at a project level, as long as forecasts remain within project tolerance, and will allocate tolerances for each management stage to the Project Manager.
The Project Board has the ability to review progress and decide whether to continue, change or stop the project.
During execution of the Project Plan, if any forecasts indicate that the project is likely to exceed the agreed project tolerances, then the deviation should be referred to corporate or programme management by the Project Board in order to get a decision on corrective action.
Has day-to-day control for a management stage within the tolerance limits laid down by the Project Board.
During execution of a Stage Plan, if any forecasts indicate that the stage is likely to exceed the agreed stage tolerances, then the deviation should be referred to the Project Board by the Project Manager in order to get a decision on corrective action.
Has control for a Work Package, but only within the Work Package tolerances agreed with the Project Manager.
During execution of the Work Package, if any forecasts indicate that it is likely that the agreed tolerances will be exceeded, then the deviation should be referred to the Project Manager by the Team Manager in order to get a decision on corrective action.
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