Transformation has become a major topic of sustainability research. This opens up new perspectives, but at the same time, runs the danger to convert into a new critical orthodoxy which narrows down analytical perspectives. Most research is committed towards a political-strategic approach towards transformation. This focus, however, clashes with ongoing transformation processes towards un-sustainability. The paper presents cornerstones of an integrative approach to social-ecological transformations (SET), which builds upon empirical work and conceptual considerations from Social Ecology and Political Ecology. We argue that a critical understanding of the challenges for societal transformations can be advanced by focusing on the interdependencies between societies and the natural environment. This starting point provides a more realistic understanding of the societal and biophysical constraints of sustainability transformations by emphasising the crisis-driven and contested character of the appropriation of nature and the power relations involved. Moreover, it pursues a transdisciplinary mode of research, decisive for adequately understanding any strategy for transformations towards sustainability. Such a conceptual approach of SET is supposed to better integrate the analytical, normative and political-strategic dimension of transformation research. We use the examples of global land use patterns, neo-extractivism in Latin America and the global water crisis to clarify our approach.