Social-ecological systems are co-evolving systems. Of particular relevance are here: (1) co-evolution of the environment and governance, (2) co-evolution of technology and governance, and (3) co-evolution of human behaviour and culture. The co-evolutionary perspective has helped to understand the processes which led to the present unsustainable situation. This paper highlights different types of learning processes which occur in co-evolving systems and explores learning processes on the macro-, meso- and micro-levels for moving onto more sustainable paths. While the literature in environmental management, ecological economics or sustainability science often refers to the need for learning processes, the conceptualisation of learning and the link to learning theories is weak. This paper draws on learning theories from psychology, social psychology, education, evolutionary economics and political science and offers a first step toward theoretical foundations of learning processes for sustainable development. An improved understanding of these learning processes will provide important clues for policy recommendations on multiple scales.