One of the most important basic functions of museums is to preserve the cultural resources of a community, not only for the present but also for future generations. In recent years, the concepts of sustainability and sustainable development have constantly come to the attention of researchers and practitioners and museums are no exception to this process. Well-managed museums not only ensure their own sustainability, but also play an important role in the sustainable economic development of different urban regions (Gustafsson and Ijla 2017) and directly influences the development of cultural tourism in a given region as well. Despite the obvious links between museums and sustainability, not much research has explored how museums fit into sustainability, and how can they become sustainable. Based on this, the main research question of my study is: How can a sustainable museum be defined based on the mission statements of European contemporary art museums and according to the value preferences of museum professionals and museum visitors? To answer the research question, the phenomenon of sustainable museums needs to be analyzed from different aspects. Qualitative research methods are applied in the dissertation: systematic literature research, content analysis, critical discourse analysis, Q-method and grounded theory based on interviews. The main scientific contribution of my dissertation are the followings: (1) Identifying 15 key sustainability thematic roles of the museums The research complements the empirical literature on sustainable museums and contributes to broadening the theoretical background. The mission of museums in this context has not been examined before. The research has shed light on the value preferences that define museums and around which they can develop sustainable strategies. (2) Identifying the objectives and roles along which different practices exist in CEE and non-CEE countries. The novelty of the research is that there has been no research on museum sustainability specifically in the context of European contemporary museums. (3) No previous study has measured and compared sustainability indicators at international level. The museums studied operate in different regions of Europe, in very different economic and social contexts. Their comparison is an important contribution to the theoretical literature of sustainable museums and museum management. (4) Identifying 3 dominant perspectives of Hungarian museum professionals for sustainable museum Research has shown that there are several possible approaches to establishing a sustainable museum strategy. Through this research we have contributed to the application of sustainability in practice. (5) Novel identification of the potential tool for enhancing sustainability: personalised museum experiences is the new technological challenge. These are areas in which museums have not yet made much progress, and the inclusion of AI in museum visits is one of the developments that could open up new horizons, and museums should therefore make a greater effort to learn about and apply these solutions. (6) Novel synthesis of the literature on sustainable museums. We have highlighted that the topic is under-researched in tourism. (7) Novel approach using the Q-method to explore the trends that characterise the engagement and mechanism of action of opinion groups. The Q-method is used to explore the trends that characterise the engagement and mechanism of action of opinion groups. (8) Identifying 3 dominant perspectives of young museum visitors for sustainable museum. The research provides insight into the differences and similarities between Generation Z opinion preferences and thus contributes to a deeper understanding of the sustainability of museums from the perspective of future museum visitors. (9) Creation of model of multi-phase museum visit, new approach to be used by museums to target visitors My dissertation has made a significant contribution to exploring the phenomenon of sustainable museum especially as this has not been studied in Hungary before.