Introduction: Climate, environment, and ecological sustainability are often in focus in public debates and are strongly associated with the concept of sustainability. These terms are sometimes used interchangeably, but environmental issues and climate change can be said to fall under an ecological perspective on sustainability. However, there are other aspects of the concept that are also relevant when striving for a more long-term sustainable future. This entry focuses on three types of sustainability—ecological, economic, and social. Other types of sustainability, such as cultural, are sometimes mentioned, but the three pillars above are widely accepted (United Nations Global Compact, n.d.). We discuss how these pillars are connected to the digitalization of society in general and the digitalization of schools in particular. School digitalization refers both to the use of digital technology and digital technology as content in education.