Global teaching and learning for sustainable development reaches from the classroom to the world outside, and is therefore a particularly interesting setting for practising transition skills. The article suggests a number of features perceived as crucial in developing young people's capability to act in a changing world and under circumstances that are difficult to predict. The suggestions are based on an empirical study of the Lund Calling project, which aimed at implementing a web-based international programme for teaching preventive environmental strategies in Swedish secondary schools. The article first presents some of the conditions in Sweden that particularly impact on young people's transition to adulthood. Related research in sustainability education is also briefly outlined. Knowledge capability theory is used to discuss results from the empirical study of the Lund Calling project, where interviews were conducted with secondary school students, teachers and headmasters. Based on these interviews, features that appear to be particularly relevant as transition skills in global learning for sustainable development include transdisciplinary action, democratic collaborative action, as well as self-directed and independent initiative. The article concludes that young people today cannot, as in earlier periods of history, base their actions entirely on the traditions of the family or community. Instead, they also need to learn to form their own communities, capable of acting at both local and global levels. Education here plays an important role in developing the necessary transition skills that enable young people to be prepared for a rapidly changing and uncertain world.