SummaryWe developed and tested a model that bridges existing team effectiveness theory with new ideas aimed at understanding the complexity of multiple team membership and virtuality. Using a sample of 60 global, virtual supply teams from a large multi‐national organization, we propose that even for new team configurations, transactive memory systems and preparation activities are critical for effectiveness. We also examined the association between members' percentage of time allocated to a team, team virtuality, and interdependence on preparation activities. Our findings suggest that preparation activities related significantly to effectiveness as mediated by transactive memory systems. Furthermore, interdependence interacted with members' percentage of time allocated to the team as related to preparation activities. Specifically, members' percentage of time allocated to the team shifted from being a positive influence on preparation activities to a negative influence as team interdependence went from relatively high to relatively low levels. We discuss implications for theory, research, and practice. Copyright © 2012 John Wiley & Sons, Ltd.
