This issue of 'On the Horizon' presents four papers that bring together two areas of 'literacies' moving up the agenda of higher education institutions in the 21st century: sustainability literacy, and digital literacy. While the authors do not use the term 'literacies', all are describing means by which they provide opportunities for learners to develop capabilities that can enable them to achieve knowledge and understanding, and thereby positive behaviours, in support of more sustainable societies. These means are digitally enabled, making use of virtual learning environments and social media alongside, in one case, face to face workshops.Higher education is on a slow journey towards re-conceptualising what it means to be a sustainable university. Sustainability of the university estate has been driven by national governments for many years, sometimes with capital funding linked to carbon reduction targets. Sustainability has long been a priority research area. But these drivers have not changed the view of thought-leaders like Stephen Sterling, who comments that higher education produces graduates with unsustainable values and behaviours (2010-11, pp.17-18) or Daniella Tilbury who says that 'universities and colleges are currently seen as contributing to the sustainability crisis and reproducing the paradigms which underpin our exploitative relationships with people and environment' (2012, p. 2).