This project aims at an improved understanding of the self-transformation of the state toward sustainability and, eventually, science-based recommendations to foster this “sustainabilization of the state”. By investigating the following overall research question, the project specifically focuses on the political-administrative system of Swiss cantons: How do cantonal states in Switzerland transform their governance toward sustainability governance? We approached this research question in three decisive steps. First, we elaborated a generic framework of the sustainable state. This framework provides an informed normative as well as analytical basis to empirically examine the “sustainabilization of the state”. The framework mainly identifies and rationalizes internal and external governance functions a political-administrative system has to accomplish in order to transform cantonal states into the direction of a sustainable state. It critically reflects and is based on concepts from transition, sustainability, and governance theories. Second, we empirically analyzed the practical forms of sustainabilization of Swiss cantonal administrations. We chose the subnational level for our research because many cantons already have installed first initiatives to foster the state’s capacity to cope with sustainability challenges, because Switzerland’s subnational level might be seen as a dynamic experimental sphere with different formations and models of the sustainable state providing the possibility to compare multiple cases under similar conditions. Based on a documentary analysis to reveal existing forms of the sustainable state in all Swiss cantons, we selected distinct cases for further in-depth inquiries. Regarding these cases, we employed a qualitative case study approach to investigate the working of sustainability governance arrangements in public administrations. Specifically, we identifyed and assessed form-specific capacities to bring forth functions of sustainable governance with reference to the analytical framework. To do so, we conducted interviews with key actors in the public administration as well as societal actors. We analyzeed the data using methods of qualitative content analysis. The third step relates to a practice-oriented level. The scientific research was continuously accompanied by a focus group with cantonal representatives. This collaboration not only strengthens the dissemination of research results, but also ensures a mutual reflection and learning process between the research team and practitioners. The project adds innovative knowledge to the sustainability governance debate in mainly four respects. First, it contributes conceptual knowledge by proposing an informed notion of governance functions of the sustainable state. Second, it provides empirical knowledge on sustainable transformation processes within the state along the studied Swiss cantons. Third, it illuminates the role of key administrative actors in transforming governance towards sustainability. Forth, the project aims for practical, socially robust knowledge to improve the capacities for sustainability governance in Swiss cantons. Hence, in addition to contributing to the scientific debate, we strive for practice-relevant recommendations for public administrations how to foster sustainability governance within public administrations.