Looking at knowledge management (KM) literature from the perspective of KM processes shows that compared with "assessment", "creation", "absorption", "storage and organization", "sharing", and "utilization", there is a gap in terms of considering the role of "knowledge active forgetting (KAF)". Similarly, the field of organizational learning has been mainly focused on the "accumulation" side of the learning, while "creative destruction" and unlearning has been less tapped. On the other hand, empirical evidences and case studies point to plenty of situations in which learning process fails, at least in part, due to the fact that the old and obsolete knowledge in organizations prohibit firms to absorb, create, or even utilize new knowledge. However, the dominance of external (opportunistic) approaches in the strategy discourse has left little free room for considering about old and obsolete knowledge from the strategic point of view. Although, the resource based approach provides us with an analytical standpoint that paves the way of considering knowledge active forgetting both theoretically and practically, this line of research seems still in its infancy. Throughout a review of the literature of strategy, we showed that the strategic approach toward "KAF", although not well developed, has some roots in this literature. Issues such as "creative destruction" (Schumpeter, 1934; Aghion and Howitt, 1990; Caballero, 1993; Duguet, 2001; Cantner et al., 2008), "organizational forgetting" (de Holan et al., 2004), "learning to forget" (Hamel and Prahalad, 1994), "avoiding preserving the past" (Hamel and Prahalad, 1994), "strategic inflection points" (Grove, 1997) are some of these issues. As it would be the main contribution of this paper, we want to legitimize the concept of KAF as a strategic issue especially in knowledge based firms, and how overlooking this issue explicitly could negatively affect the implementation of other strategies. Finally, some theoretical questions and practical challenges have been discussed as future research and actions in the field of strategy.