In my thesis, I examine and compare the methodology of set design in film and theatre from a designer's perspective. The aim of my research is to understand how designers work with space in different situations and to identify the differences between the working methods in theatre and film. To obtain a comprehensive picture, I conducted live interviews with production designers who work in both theatre and film. My goal is to explore where they draw inspiration from for a particular project, as well as to identify the differences that arise in the design process between films and stage plays. Additionally, I delve into the topics of space, spatial communication, mapping, spatial psychology, and perception. The choice of my thesis topic is motivated by my own future career as a production designer, with the hope that this study will contribute to my professional development and provide a broader understanding of the field.