Transformations of economies, norms and social relations are required to achieve the sustainability of earth systems as part of wider sustainability. This Special Issue examines how sustainability transformations are shaped by processes, practices, and pathways as sets of collective action. The contributions showcase interdisciplinary research, empirical studies, and community engagement with may arguing that such holistic approaches are essential to achieving sustainable transformations. Here we highlight both critical barriers, such as economic constraints, political resistance, and justice conflicts, and mechanisms that enable systemic change, such as scaling up, institutionalizing sustainability innovations, strengthening multi-level governance, and participatory decision-making. Future research requires on understanding the stages and scales of transformation, identifying power dynamics and governance structures that enable systemic change, and the importance of integrating co-produced knowledge into policymaking.