Critical To Quality Tool

The Critical to Quality Tool: What It Is & How to Use It


In the world of Lean Six Sigma, the “Critical to Quality” (CTQ) tool is used to identify and assess the factors that are most important to the quality of a product or service. In other words, it helps you figure out what needs to be done in order to meet or exceed customer expectations.

The CTQ tool is used during the Define phase of a Six Sigma project. It can be used individually or as part of a team, and it’s a relatively simple tool to use. Here’s a quick overview of how it works.

How to Use the CTQ Tool


1. Identify your customer base and determine their needs and expectations. This step is crucial; if you don’t know what your customers want, you can’t possible give it to them. surveying your customer base, either through one-on-one interviews or via an online survey, is the best way to gather this information.

2. Once you have a good understanding of your customer’s needs, start brainstorming what is critical to the process that creates the value for that customer and also what would address those needs. Make sure to involve as many people as possible in this step, as different people will have different perspectives on what might work best.

3. Once you’ve generated a list of possible critical items (Voice of the Customer), it’s time to start narrowing things down by assessing which solutions or elements are critical to quality. To do this, simply ask yourself, “Which of these solutions, if not handled properly, would result in an unacceptable product or service?” The answers to this question will help you identify the CTQs for your project.

4. Once you’ve identified the CTQs for your project, it’s time to determine how you’re going to measure them. This step is crucial because you need some way of knowing whether or not your solutions are having the desired effect on quality. Create measurable targets for each CTQ and brainstorm ways to track progress towards those targets.

5. Now that your CTQs and corresponding measurement targets are firmly established, it’s time to put your plan into action and start working towards improving quality! Implement your solutions and track your progress regularly; if things aren’t going as planned, don’t be afraid to go back to the drawing board and make necessary adjustments until you’re satisfied with the results.

[repeat steps as necessary]



The Critical To Quality tool is an essential part of any Six Sigma project; it allows you to help ensure that you’re meeting or exceeding customer expectations by identifying the most important factors affecting quality. Although it’s a relatively simple tool to use, it can make all the difference in the success of your project; so if you’re working on a Six Sigma project, make sure to give it a try!

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Reagan Pannell

Reagan Pannell is a highly accomplished professional with 15 years of experience in building lean management programs for corporate companies. With his expertise in strategy execution, he has established himself as a trusted advisor for numerous organisations seeking to improve their operational efficiency.

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