Recently, the field of Knowledge Management has seen some movements towards sustainability and more responsible business practices. Especially sustainability has become a hot topic for almost every organization. In this paper, we try to locate the concept of sustainability in the field of Knowledge Management. We argue that lived sustainability is built upon relatedness (the holistic understanding of interdependence and interconnectedness of complex systems) and futureness (adopting a long-term perspective for the management of organizations) that together promote sustainable organizing from the inside-out. We find that in particular two streams, Responsible Knowledge Management and Spiritual Knowledge Management, have taken up ideas that potentially lead to sustainable Knowledge-based Management. Those streams emphasize various forms of non-rational knowledge as a necessary, but previously underrepresented aspect of knowledge, as a counterpart to the instrumental-calculative rationality that has become predominant in the study of organizations and organizational knowledge.