Diversity has long been assumed to have positive effects on organizational and group performance. Empirical evidence to date fails to support this assumption. The present paper provides a preliminary examination of the effects of diversity on a group task. The data are part of an ongoing study, where individual demographic information and task performance of groups have been collected. Diversity indices for racial and gender diversity are examined to determine the effects they might have on task performance. The instructions of the task, however, vary. In one situation, 2 groups are instructed to compete with one another. In the other situation, 2 groups are instructed to cooperate with one another. T-test A NOVA, and ANCOVA results consistently indicate that task-type influences changes in group-based outcomes. The implications of these preliminary results and future directions of research are discussed. © 2002 Plenum Publishing Corporation.