This paper describes an approach to teaching systems thinking and associated capacity building for a team of professionals and managers from a developing country (Vietnam), engaged in the sustainable management of a world biosphere reserve. Vietnamese environmental and development managers and UNESCO were attracted to a systems approach to managing the Cat Ba Biosphere Reserve because it offered a way to address components of sustainability holistically, while transcending organisational and disciplinary ‘silos’. Key features of the training approach include learning as a group of professionals, with senior organisational support and commitment to apply systems approaches in the workplace; enjoyable adult learning approaches tailored to the needs of participants; complementing teaching of systems thinking and techniques with participatory methods for working with the participants in developing solutions to their sustainability issues; and building in evaluation at every stage, through participatory methods taught in the course. The paper highlights the importance of teaching systems thinking and provides an example curriculum and teaching strategy based on adult learning principles. Copyright © 2011 John Wiley & Sons, Ltd.