This paper introduces a knowledge-in-practice framework for understanding the nature of work from a knowledge perspective and uses the framework to peer into the black box of knowledge management (KM) and explore the relation between KM activities and performance. The knowledge-in-practice framework describes knowledge characteristics of work practices along two dimensions: tacitness and learnability. We propose that adopting KM activities that match the tacitness and learnability of organizational work settings will have a positive effect on desirable performance targets for each work environment. We identify patterns of KM activity that are believed to be maximally effective within each work setting.