This thesis explores the implementation of lean management in ROCKWOOL Adriatic Ltd, a company that is part of a global group known for producing stone wool insulation materials. Lean management, as a modern approach to management, is focused on waste reduction, resource optimization, and continuous improvement of business processes. The paper analyzes how lean management principles have been applied in ROCKWOOL Adriatic and the results achieved following the implementation, including increased operational efficiency and improvements in organizational culture. The work begins with a review of the theoretical foundations of lean management, its historical development, and key principles such as creating value for the customer, optimizing value streams, establishing continuous flow and pull systems, striving for perfection, and empowering employees. It also examines the key methods and tools of the lean approach. As part of the research, an interview was conducted with the manager of ROCKWOOL Adriatic Ltd, providing a detailed insight into the challenges the company faced and the benefits derived from applying this system. Special emphasis is placed on adapting lean methodology to the specific characteristics of the company and the regional business culture. Despite the challenges, lean management has proven to be a crucial tool for achieving long-term competitive advantage and sustainable operations at ROCKWOOL Adriatic Ltd.