Diversity can have positive and negative effects on team decision making. Text communication has been put forth as one solution to addressing this duality of team diversity. Unfortunately, the empirical results have been far from conclusive. We believe that resolving such inconsistencies is crucial to developing a more complete understanding of the use of communication technologies. To accomplish this, we developed a research model based on media synchronicity theory. We empirically tested this model by conducting a laboratory experiment with 46 teams, consisting primarily of men and women self-identified as Caucasians and Asians, performing a decision-making task. The results show that the type of diversity matters. Text communication improved knowledge sharing (i.e., conveyance) and knowledge integration (i.e., convergence) in racially diverse teams but impaired both in gender diverse teams. Knowledge integration was more important to decision quality when racial and gender diverse teams used text communication (but the importance of knowledge sharing was not affected by the communication medium).