In this competitive era, where all businesses want to be among the best both in terms of cost and quality are struggling hard to identify ways to improve their processes. Constantly challenged with downward price pressure and increased quality Six Sigma is one of the methods to improve quality and reduce cost. Six Sigma intends to achieve 99.99% precision by attaining 3.4 defect parts per million. These days it has not just remained a tool to reduce variability but it helps to align the business processes by engaging management at all levels. Using DMAIC model it helps to identify the customer needs and perception first, and then measure how far the process is in control in respect of the customer requirement, followed by analysing the reason for non-compliance, then looking for improvement options available which is best suited and then try and maintain the process. It requires involvement of people at all levels. Six-Sigma takes into account the individual projects focused at improving one part of the organisation at one time. External master black belts and back belts come into the organisation to implement the various projects and for supervision. Six-Sigma has its origin in Motorola where it leads to huge business improvements. In order to implement Six-Sigma it is important that the company has taken some qualitative initiatives beforehand which make its implementation easier. Application of Six Sigma leads to huge benefits and leads to organisation with best in class products; however its implementation incurs huge costs, so companies whose main issue is quality should only implement it. For instance sectors like IT where main issue is speed, implementing Six Sigma is not worth. The workforce of the organisation are often ignored while its application which sometimes leads to its failure. People in the organisation get de-motivated while seeing other people taking over the processes. They feel they have lost the power and since they play an important part, so when they are ignored it leads to failure of Six-Sigma project. People generally resist change because it involves them to come out of their comfort zone, they often don’t understand the potential benefits of its implementation.