>You will certainly notice that talks that go overtime make for a terrible experience for everybody. So don't do that. (You'll need strategies. The simplest is

>You will certainly notice that talks that go overtime make for a terrible experience for everybody. So don't do that. (You'll need strategies. The simplest is to have "landing points" in the talk, so that if you see that time is running short, you can skip some material to get to a landing point. Obviously, the conclusions slide ought to be a landing point.) I won't say I've never gone a few minutes over when there's a break coming up and the audience is engaging. But, yeah in general, it's especially rude when the next speaker is waiting to get setup, and that time they're left with 1 minute to plug in will be the time something goes wrong. You should have a decent sense for pacing of the talk anyway but, as you say, you should also know which material lends itself naturally to "in the interests of time, I'm not going to spend a lot of time on this topic today but we can talk afterwards if you're interested sort of thing." Conference talks are also different lengths and they've tended towards shorter over time. So, even if you can adjust on the fly to some degree, consider not using the same deck for a 30 minute talk and a 50 minute one. (I'm actually a fan of talks that are on the shorter side in general.) I have mixed feelings about Q&A in the session itself in general for a lot of reasons. But you need to keep things from getting too diverted or getting down the "more a comment than a question" path. (Which is part of the mixed feelings--it's hard to cut off without seeming a bit rude.)