The topic of this thesis is "Mapping in the supply chain - a tool for analyzing and improving the service process". The paper tries to explain what mapping in supply chains actually is, how it works, and tries to explain how it works in the chosen company. In the first part, the concept of mapping in supply chains will be clarified, what supply chains actually are, what are their components, what types of maps exist and what their tasks are, and the concept of Value Stream Mapping (VSM). Mapping in supply chains or just in some processes is very important so that tasks are carried out on time and when it is really necessary, and so that it is possible to know at all times who has what role in the process. After getting acquainted with the concepts of mapping in the supply chain and VSM, in the second part, mapping will be explained and shown using the example of McDonald's. The first step towards creating a map of the future state is first to draw a map of the current state that shows us where the company is currently and what can be improved and changed. The map of the current state is first sketched by walking through the restaurant and getting to know the space. Once the map of the current state is drawn, only then can one see if there is room for improvement. Based on it, a map of the future state is drawn, which, with the help of kaizen practice, creates solutions for problems that were observed earlier. When that is done, then it is possible to implement all the changes that have been established. The paper will present three hypotheses that will have to be either confirmed or rejected, and at the very end, suggestions for improving the process in the restaurant will be proposed.