As organizational environments become more turbulent and as managers spend more time in meetings in an effort to deal with that turbulence, using information technology to support meetings has become more important. This paper reports on an experiment that compared meetings supported by information technology to meetings with conventional manual support only. The experiment differs from most previous group decision support system (GDSS) experiments in that solutions to the task it used could be objectively scored, it introduced assigned leadership as an independent variable, and it is the first GDSS experiment to compare use of a subset of the University of Arizona GroupSystems GDSS tools to manual group methods. In addition to a communication condition (GDSS or manual) and assigned leadership, the experiment also investigated the effects of anonymity on group process and outcomes. The experiment found that GDSS groups were less likely to reach consensus, took more time to reach a decision, and had more equal levels of member participation than manual groups. No main effects were found for assigned leadership or anonymity.