The present thesis focuses on educational leaders’ perceptions of their occupational well-being and work as leaders. The specific research questions are as follows: (1) How do educational leaders in Finland perceive demands and resources that influence their occupational well-being? (2) How can educational leaders’ work in Finland be conceptualised from an ecological systems theory perspective? The thesis comprises three peer-reviewed sub-studies, the data for which were drawn from the larger Teacher and Student Stress and Interaction (TESSI) project. Data for the sub-studies were collected from 18 day-care centre directors (Sub-study 1) and 76 elementary school principals (Sub-study 2) via questionnaires, plus semi-structured interviews with 22 school principals (Sub-study 3). Qualitative content analysis was used to analyse the qualitative data in all three sub-studies, and the quantitative data were analysed using correlations and nonparametric tests in the first sub-study. The results indicate that educational leaders’ perceptions of their work can be described through personal and job-related demands and resources, contextual factors and ecological systems. Most extensive demands on educational leaders are related to interpersonal relationships and interactions with and between different stakeholders, and also entail dealing with elements or issues that leaders cannot influence or control. The results highlight the importance of social support in the workplace, as well as support from family and friends in personal lives. Furthermore, both physical and emotional self-care are crucial for balancing demand and resources to maintain well-being. Overall, the results deepen the understanding of educational leaders’ occupational well-being and work. Based on the results, practical suggestions are offered on how educational leaders’ well-being could be promoted on different levels of their work-related ecological system and who could promote it.