Information system development involves the coordinated application of business and information technology (IT) professionals’ expertise. However, knowledge sharing between these two groups can be challenging. The problem is even more pronounced for projects involving external IT consultants with whom the business professionals have no prior collaboration. While previous research has studied various antecedents of knowledge sharing such as source, recipient, communication, and relational characteristics, it is often not clear how they may be manipulated to facilitate sharing. For this purpose, this paper studies the phenomenon from the social interdependence perspective, which suggests that goal, task, and reward interdependencies affect the extent of knowledge sharing in ISD project teams. Findings from a survey of 95 project teams indicate that goal, task, and reward interdependence are significant in determining knowledge sharing, which in turn influence project performance. Additionally, task interdependence partially mediates the relationship between goal interdependence and knowledge sharing. These results thus help to identify antecedents that are more tenable to managerial intervention. Implications of these findings for research and practice are discussed.