Having seen Six Sigma Methodology and Lean Six Sigma tools elaborately, it is appropriate to look into some case studies on Six Sigma implementations. We present two case studies on Six Sigma implementation by two leading companies in this section. These studies reinforce Lean and Six Sigma Concepts as well as demonstrate the the tools used by them for implementing the same. The importance of achieving operational excellence by way of reducing defects and variations in processes as well as eliminations of non value adding steps in processes can be inferred from these case studies. One more case study on “Mumbai Dabba walahs” also presented at the end of the chapter to clearly demonstrate that Six Sigma is a tool not only for coporates but also it is for common man who are capable of achieving Six Sigma level in their services in execution of their daily tasks by fulfilling their customer needs.