Universities play an important role in shaping the future of the world society in terms of sustainable development by generating new knowledge as well as contributing to the development of appropriate competencies and raising sustainability awareness. During the last years, many universities have undertaken activities for implementing Higher Education for Sustainable Development (HESD). Many have asked which key competencies are most relevant for sustainable development and hence should be developed in future-oriented higher education. Different approaches for the selection of sustainability key competencies have been developed, but there is little international agreement in the debate around the most important key competencies. Consequently, this paper asks which individual key competencies are crucial for understanding central challenges facing the world society and for facilitating its development towards a more sustainable future, and thus identifies those competencies which should be fostered through university teaching and learning. The empirical design of the study is related to a Delphi study in which ‘sustainability key competencies’ are defined by selected experts from Europe (Germany, Great Britain) and Latin America (Chile, Ecuador, Mexico). The results show that twelve key competencies crucial for sustainable development can be identified; the most relevant ones are those for systemic thinking, anticipatory thinking and critical thinking.