The continuous process optimization of every company is one of the central tasks of operational management. The assumption that the organizational structure and processes of companies can only be understood as static and unchangeable is misleading. On the contrary, improving process performance, reducing time and costs, and adapting to changing customer expectations are equally demanded. By comparing Six Sigma and Kaizen, two possible management concepts, the book provides a good insight into the methods, their opportunities, and potential problems in application. This book is helpful for all readers who want to engage with the methods and compare different management concepts for the first time.