The topic of this undergraduate thesis is „Lean management – business philosophy of successful companies“. In the first part of the thesis, the meaning of the concept of Leanmanagement and the concept of Lean production are defined, followed by the history of the development of Lean management as well as its characteristics and principles. Using five basic principles, the business philosophy of this type of production is explained, which includes the fundamental step of successful Lean transformation, which is value chain mapping. Companies use it to create a visual guide to allthe components needed to deliver products or services, withthe goal of analyzing and optimizing the entire process. The second part of the thesis includes activities in the business process with their division into activities that add value to the product and those that do not add as well as seven types of losses called muda, which are inefficient forms that the Lean manufacturing system seeks to eliminate. In the third part, ten elements of the Lean system are listed and explained, namely flexible resources, cell production, Pull system, Kanban, small series, fast machine preparation, uniform production, quality at source, preventive maintenance and supplier network. In the following, important Lean tools such as teh Pull system, Kanban, Just-in- time, Jidoka and 5S are developed. Lean tools are designed to reduce muda in organizations and improve quality control. In other words, they seek to eliminate processes that are not valuable.