The concept of sustainable development is a foundational concept in educational contexts which seems to be interpretable in various terms. With reference to four syllabuses in the Swedish curriculum, our aim is to identify possible ways of conceiving how the concept may be developed in relation to perspectives bringing forth the relation between "knowledge about" and "knowledge for sustainable development". In the analysis, Bernard Williams's distinction between "thin" and "thick" concepts is applied. With this analysis, a phronesian strategy is suggested to bring world-guidedness and the action-guidingness together within a holistic interpretation. The phronesian strategy will require action of the pupils and sensitivity to the individual and society as a whole. The four syllabuses in social science seem to combine theoretical perspectives with more or less explicit implications of practical and action-oriented educational methods and goals. However, an individualistic attitude and approach to problems and solutions in our world seems to be favoured, which pedagogically could be questionable.