This section examines the role of human factors in building maintenance. Since maintenance involves a complex interplay of interactions among people—both direct and indirect users of the built environment, the architectural systems being maintained, tools, and the surrounding environment—the part aims to demonstrate how interactions within socio-technical systems can be improved through the HFE approach. It considers the physical, cognitive, and organisational aspects of maintenance, with a focus on both effectiveness and efficiency. At the same time, it emphasises the importance of ensuring the safety and well-being of all involved.