Sustainability transitions research proposes fundamental changes of societal systems' organization to overcome persistent societal challenges, such as climate change or biodiversity loss, and allowing systems to become more sustainable. This thesis addresses an underlying tension in sustainability transitions research: between transitions as an open-ended process of fundamental change and the normative direction of this change: sustainability. In doing so, three themes so far under-explored in sustainability transitions scholarship are in the focus of the research: individual agency, normativity and transdisciplinary collaboration. Thereby, the thesis aims to strengthen process-oriented and potentially transformative approaches to sustainability transition research, in contrast to primarily descriptive-analitical approaches. Transition management as a recent and salient example of transdisciplinary transition research is chosen to provide both, research framework and application context. Based on conceptual-theoretic, empirical case study and reflexive work, three main results are contributed: First, a psychologically enriched understanding of individual and sustainability related agency in conceptual and empirical understandings of transition management is developed. This builds on two perspectives: a psychologically enriched capability approach as well as the analysis of social effects (social learning, empowerment and social capital development) of transition management to capture sustainability oriented agency increases. As second main result, normative considerations, namely sustainability, are included into transition management on conceptual and empirical levels. Therein, substantive, procedural and intentional aspects of sustainability are combined: Substantive aspects are covered by proposing capabilities, behavioral freedoms to live a valuable life, as normative yardsticks to measure developments. Procedural aspects include a detailed understanding of facilitating a learning journey towards making sustainability meaningful in the local transition management cases and setting up experiments for its realization. Intentional aspects are addressed by linking social effects of transition management to awareness, motivations and feelings of responsibility towards sustainability. As a third main result, the transdisciplinary collaboration in transition management of creating an arena as an interactive learning space is conceptualized and explored, as well as the roles of the researchers therein. Key issues of this learning space, the community arena, are drawn out and ideal-type roles and activities of researchers in addressing these issues are proposed and empirically analyzed. As overall synthesis of results, ten principles of sustainability transition management are proposed.
