Tollgate Reviews are normally carried out at the end of every step in the DMAIC Process. That is, they will be carried out at the end of each of the Define, Measure, Analyze, Improve and Control stages.
For projects based upon the DMADV methodology, tollgate reviews would be established after each of the 5 phas
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es: Define, Measure, Analyze, Design and Verify.
Tollgate Reviews help determine whether all the goals within each stage have been achieved successfully and whether the project can progress to the next stage.
The diagram on the right indicates how a tollgate review is carried out at the end of each stage. The red arrows indicate when the goals have not been met and the activities within the stage need to be re-visited.