Introduction and overview of the broad topic of sustainability. The topic of sustainability has been widely discussed for several years. But what does sustainability actually mean? How is a concept implemented and with what tools? This book familiarizes readers with the relevant terms, concepts, and areas of sustainability. After a historical introduction, specific focal points and application areas are presented. By examining economic, ecological, and social aspects, the complexity and range of applications of sustainability are addressed. The 3rd edition has been expanded to include the three guiding strategies of sustainability - sufficiency, consistency, and efficiency. In discussing sustainability in companies, the topics of eco-efficiency and eco-effectiveness, as well as socio-efficiency and socio-effectiveness, have been added, along with general updates.