Six Sigma is now being used in the service sector as well. It helps to improve the quality of the services rendered. Six Sigma, It is a rigorous and disciplined methodology that uses data and statistical analysis to measure and improve a company's operational performance by identifying and eliminating "defects." Six Sigma proves to be perfectly suited to the needs of the service industry like Banking, which is in constant contact with customers and has customer delight as its top priority. In the „define‟ phase of DMAIC (define, measure, analyze, improve and control), Six Sigma professionals define the objectives and boundaries of a particular business process, in consultation with the employees and senior management. In most banks, customer satisfaction is the main objective, making it necessary to define all the processes that involve customer interactions and directly affect customer satisfaction & Six Sigma implementation will be helpful.