Sustainable development (SD) has undergone continuous evolution since its institutional emergence approximately 50 years ago. In light of persistent global challenges, there is increasing recognition of the need to expand the prevailing SD paradigm to include a cultural-spiritual and inner dimension. From this perspective, the current socio-ecological crisis may be understood as a manifestation of a deeper cultural-spiritual crisis. This chapter proposes an Integral Sustainable Development approach informed by anthroposophy. It begins by outlining key definitions and historical developments in the discourse on sustainable development. It then explores the implications of incorporating a cultural-spiritual dimension, which calls for a renewed understanding of human nature in relation to the environment. Anthroposophy, developed by Rudolf Steiner, offers a relevant framework through its emphasis on three interconnected human faculties—thinking, feeling, and willing—which shape individual and collective activity. Steiner’s concept of the Threefold Social Order is also examined, distinguishing three interdependent yet autonomous spheres of society: the cultural/spiritual, the legal/political, and the economic. These are associated respectively with the guiding principles of freedom (Liberté), equality (Égalité), and solidarity (Fraternité). Within this context, the chapter introduces the idea of appropriate anthropocentrism embedded in a holocentric ethic, forming the foundation of Integral Sustainable Development. This approach integrates the cultural-spiritual dimension into the established pillars of sustainability—ecological, social, and economic—through the concepts of world-viewing, world-sensing, and world-acting. The chapter concludes with four case studies of anthroposophically inspired enterprises that exemplify the practical application of Integral Sustainable Development principles.