Mass gatherings and special events are commonplace in the U.S. and require the coordinated efforts of a multitude of people, including EMS, to make for a successful event. As the medical director of the EMS, it is important to understand not only the medical problems that could occur at these events but also a basic knowledge of the business behind their planning. Constant interaction with event promoters and sponsors can help the director get a feel of the safety concerns and how funding of the event will occur. These interactions can help directors determine the size, recurrence, and risks of the event providing them with the necessary information of how much manpower will be needed and the costs of the services to be provided and will give them the power to have successful negotiations with a well thought out event plan.