The purpose of this research was to investigate how the implementation of lean production can be effectively planned and managed. Based on a literature review of the existing literature on lean, change management and lean implementation, a comprehensive framework for lean implementation which considers the technical, organizational and change management aspects of lean implementation was developed. Four significant elements of this framework were chosen for further investigation. These elements concerned the importance of top management support and active leadership, basic operational stability, a culture for problem solving and continuous improvement, and lean knowledge and training, to a succesful lean implementation. Four propositions to guide the research were formulated based on these elements. A case study of a lean implementation project in Grundfos Manufacturing Hungary was conducted to test the propositions. The case study confirmed the importance of the four elements, as well as the importance of availability of resources and realistic and strategic goalsetting, to lean implementation success. A revised framework based on the case study findings was presented.