Organizations are still confused about tacit knowledge principles, conceptualization and applications. In this chapter, authors approach how tacit knowledge can be valuable for practical decisions and implementations, from theoretical and practical points of view. Approaching from the theoretical view, tacit knowledge definition was discussed, as it results from a conceptual development already adopted for several decades. From practical analysis, actual and future trends arise, as its applications and influences were consolidated, in the perspective on associating tacit knowledge with explicit, for planning, designing and implementing real businesses solutions. Modern competitive features and propositions, such as big data, information technology insertion and startups entrepreneurships are also discussed, serving as an orientation for new studies, as tacit knowledge plays a differential role for new ages of value-aggregation arrays.