The concepts of Lean Manufacturing and Six Sigma have been applied in manufacturing companies with greater frequency. However, there are few records of its implementation in companies in the service sector. This sector in Peru represents more than 50.6% of the country's Gross Domestic Product and it is composed mainly of SMEs. Nevertheless, this kind of businesses are characterized by having low productivity, lack of organization and monitoring of performance indicators to make good decisions. Therefore, different techniques are required to maintain their efficiency and productivity over time to meet the expectations of the consumers. In this research, the objective is to propose a management model by applying Lean Six Sigma in order to improve the performance of an SME in the professional services sector. Through the DMAIC process, a diagnosis of the company was carried out, finding the...