This paper describes research in progress to empirically test the Media Synchronicity Theory (MST) (Dennis et al. 2008). We conducted an experiment consisting of 55 individuals organized into 13 different teams. The teams were assigned to use a lower synchronous medium, a higher synchronous medium, or a portfolio of media. The teams worked together on a new hidden-profile task, and several variables relating to communication performance were measured. The results of the initial study indicate support for the main hypotheses of the paper and the theory. Teams that used a portfolio of media outperformed those teams that used only one type of medium. However, additional data collection is necessary for significance testing.