Why does a team member prefer some colleagues to others in information seeking? Past literature suggests that the physical accessibility of a knowledge source, the information quality of the source, and relational concerns influence such a choice. This study extends past literature by suggesting that formal structural factors are also important. Particularly, job interdependence, competition, and supervisory relationships are hypothesized to affect information-sourcing frequency. Our social-network analysis of an information systems project team indicates that formal structural factors are important to the development of informal networks and the perception of the information quality of a source. They have direct and indirect impacts on sourcing behavior. Implications for information systems project management are discussed.