I had two situations recently where I have been asked for what options you have when you are doing a presentation with multiple presenters, each having their own PowerPoint slides. In one situation, there are two presenters doing a session and they will be switching back and forth between their slides but they aren't sure when the switch will take place based on the audience reaction to the content. In this case, I suggested that they ask the A/V company to supply a projector with two computer inputs (many of the mid to upper range projectors have multiple computer inputs). Each presenter will connect their laptop to one of the inputs on the projector. During the presentation, when they want to switch between the slides, they will simply switch the input on the projector to display the correct laptop input. The other situation is a panel discussion I am involved in. There are three of us who are using PowerPoint, but it is sequential and we know when the presenters will switch. So in this case, we are going to load all of the presentations onto my laptop and we will just hand the remote to the next presenter when it is their turn. Every multiple presenter situation will be different and you need to think of what will look as seamless as possible for the audience when you look at how to set it up.