Introduction: In this paper, we discuss the link between information sharing and organizational knowledge production in two very different organizations; a company that handles insurance claims and a small, entrepreneurial hi-tech company. We suggest that this link has not been adequately addressed by studies of information behaviour, though a number of recent papers have proposed that human information behaviour research should appropriate methods from workplace studies and computer-supported cooperative work to provide a richer account of organizational information and knowledge work. Method: Two case studies of sharing practices in Finnish firms were carried out. Results: The overall analysis has allowed us to explain how and why organizational information sharing happens in terms that go beyond the cognitive and descriptive accounts of our earlier studies. Conclusions: Information behaviour is a repertoire of actions and operations and judgements about timing and ethics that are brought into play across work cycles and routines. From this perspective, the duality of organizational knowledge becomes clear: it is both individual and collective judgements about how to behave, and the incremental outcome of these judgements, embedded in decisions that support the objects of activity systems.