The aim of this thesis was to find out what kind of role and responsibility the supervisor has in the change management, as well as what the supervisor should notice in change from Lean's point of view. The work was started from the perspective of the work of the supervisor in the expert organization, which at the same time served as a delimitation to the topic of the work. The most important themes in the work are supervisory work, change management and Lean. The theory section processed work and role of a supervisor, change management and its challenges, and Lean management and its key tools. The research was carried out as a qualitative survey, which was built based on the theoretical knowledge discussed in work. Based on the results of the study, the role of the supervisor in change management is to support and encourage employees. It is the responsibility of the supervisor to ensure proper and timely communication as well as planned export through change throughout the process. The presence of a supervisor is perceived as important, but the role of the supervisor should not be too big or dismissive. When the supervisor is open and participatory, the amount of change resistance among employees can be estimated.