Design for Six Sigma (DFSS) is a separate process management methodology related to Six Sigma. While Six Sigma and Lean Six Sigma are used for process improvement, Design for Six Sigma methodology primarily aims at product development from the ground up. It is used to design or re-design a product or service from the ground up. The expected process Sigma level for a DFSS product or service is at least 4.5, but can be 6 Sigma or higher depending the product. These methodologies are similar, however, they do differ in a number of aspects. This methodology is widely used in engineering and manufacturing.