Air Traffic Control communication is an act of collaboration between pilots and controllers, and the success of this collaboration depends on how smoothly speakers and listeners work together. For example, we have found that the way controllers deliver ATC messages influences how easily pilots understand these messages, which in turn determines how much time and effort is needed to successfully complete the transaction. We first introduced a collaborative framework for investigating air ground comunication and then describe a set of field and laboratory studies that investigated ATC communication. We focused on the impact of ATC message factors (e.g., length and timing) on the cognitive processes involved in ATC communication. These studies also illustrate how the collaborative framework helps analyze the impact of proposed visual data link systems on ATC communication. Examining the joint effects of communication media, message factors, and pilot/controller factors on performance should help improve air safety and communication efficiency.