The present study investigated whether the anticipation of membership change affects group performance. Thirty-two triads were asked to collaborate on an assembly task. We manipulated the anticipation of membership change by warning or not group members. As expected, results showed that the anticipated membership change interfered with team performance, due to the difficulty of building transactive memory. The anticipated membership change inhibited expertise specialization between group members from the start of the collaboration. These findings are consistent with the view that membership change is not always detrimental to group performance: its impact depends on whether it is anticipated or not.