The present study aimed to investigate elementary school principals’ work from the ecological systems perspective and which elements of their work are experienced as demands or resources. Semi-structured interviews were conducted with 22 principals. Qualitative content analysis was used to analyse the data. The results show that the way principals experience their work is individual and influenced by several internal and external factors. Some of the most extensive demands appear to be related to interaction with different stakeholders in situations where principals have the role of mediator in solving conflicting situations. Challenges also seem to arise in dealing with elements or issues that principals cannot influence or have no control over. Principals’ current perception is influenced by their education, work and personal histories and future vision. The results also indicate that principals need in-service training concerning social interaction and human resource management, such as how to act in conflicting situations, interact with different personalities and get the entire school community to develop and work for common goals. In addition, our findings suggest that offering support to principals through, for example, mentoring programmes during their first years could reduce the pressures they face and help them concentrate more fully on relevant tasks.