There are good chairs and bad. Surprisingly (or not, this is academia, after all..) there’s little guidance. I’ve put together a list:

1. Start as you mean to go on. Remind speakers to keep to time (see next point) and encourage questions from all attendees (see point 3)
2. Control time with an iron fist – and let speakers know in advance that you plan to. Letting the big old dogs in your field ramble on at the expense of others’ time is unfair to younger researchers. Introducing yourelf to speakers early on email is a great place to mention this and it also kicks the relationship off well
3. Do you want to create a lively, inclusive spirit of debate? If so, lead the way –
4. Do your homework. Simply reading the speaker’s title and name from their slide is disrespectful (how would you feel?)
5. Take responsibility for the sound. You are probably nearest the speaker stage, so if the sound is muffled, or inaudible to you then others will be really stuggling. if a mic has been turned off, or not clipped on, step in, apologise, and rectify it.
6. Pay attention during every talk, not just the ones your mate’s giving. This is because you need to…
7. …. make sure you have a reserve question for every speaker, in case there aren’t any. This is especially true for students, who will have put in a lot of work and stress to give yheir first international presentation.
8. You are the chair. Police the questioning accordingly. If the same people are crowding other, junior, less confident questioners out, simply pass over them or gently but firmly make sure they wrap up. Make sure all questions can be heard, clearly, by the audience.
9. Stay impartial. It may be more useful to imagine yourself an editor, not contributor, to the debate.
10. If a debate turns toxic, cut that shit out.
11. Finish by thanking all speakers and the audience.