The C4 method was developed by David Veech and Mike Kirkby to encourage problem solving in the workforce within any type of business. Implementing the method relies on utilizing the C4 card or a worksheet in an A3 format. The goal of C4 is to identify small, daily improvements that are easy to remedy yet still need a problem-solving process to complete.

Usually, C4 is used with quality circles and improvement teams. The C4 method is very similar to the PDCA cyclePlan, Do, Check, Adjust – However, C4 aims to describe the plan step more thoroughly in the beginning to make following decisions and actions easier. The elements that make up the C4 problem solving method are:

  1. Concern – Using gathered data, describe the corresponding issue that must be resolved.
  2. Cause – Identify the cause(s) of the problem by using a cause and effect diagram. Prioritize issues that need to be resolved as soon as possible.
  3. Countermeasure –Implement a short-term solution that can be revisited for revisions if need be later on.
  4. Confirm – Revisit the countermeasure and make sure it was successful at solving the problem. This is the time to make successful short-term solutions into long-term solutions that will solve the problem permanently.

Overall, the C4 method is much simpler than Six Sigma’s standard Define-Measure-Analyze-Improve-Control method, also known as DMAIC. This makes it much easier to implement when a small issue arises that needs this kind of lean problem-solving intervention.


Free E-Book

Six Sigma Guide

Learn about this data-driven approach to improving quality and reduce waste.


Free E-Book

Lean Manufacturing

Minimize waste and maximize efficiency with our step-by-step guide.


Free E-Book

Continuous Improvement

Learn how to make continuous improvement a part of your company culture.

Other FREE Resources:

Helpful Resources