New computer-based communications technologies make possible new or expanded forms of group work. Although earlier researchers suggest that scant social information in these technologies might cause status equalization in groups, no experimental test of this phenomenon has been made. In a laboratory experiment, we compared face-to-face communication with electronic mail in decision-making groups whose members differed in social status. We examined status in two ways: by varying the external status of group members, and by varying the decision task to manipulate expertise. When the groups made decisions in face-to-face meetings, the high-status member dominated discussions with the three low-status members. Also, the high-status member more often was a "first advocate" in the face-to-face discussions, and first advocates were more influential than later advocates. These status inequalities in face-to-face decision making were pronounced just when the high-status member's expertise was relevant to the decision task. When the same groups made comparable decisions using electronic mail, status and expertise inequalities in participation were reduced. A striking and unexpected result was that "first" advocacy was shared by high- and low-status members in discussions using electronic mail. This behavior resulted in increased equality of influence across status and expertise. We discuss the implications of these results for research and for design of new communication technologies.