This thesis is an industrial application of Six Sigma to enhance the OEE of a production line. It includes the review of literature about Six Sigma, a case study, and four interviews to managers who dealt with Six Sigma. Six Sigma is a flexible method for improved process output performance and enhanced business leadership. It provides a set of tools to solve problems through projects that follow the DMAIC cycle: definition of the problem and the goal, measurement of the output, analysis of the problem’s causes, improvement of the process, and sustainability control of the enhanced process. The customer plays an important role as his requirements are the starting point for definition of goals.