I did a LOT of post-doc interviews: ten labs, eight institutes, on three continents. I've done two in a day, and one in a day and a half. I've spoken with lab members who barely spoke English, and others who could out-geek me. And having done all this, I would like to present my ideal post-doc interview schedule.
Before any flights are arranged, there should be a phone interview. This is in part to make sure there is mutual interest in terms of project and personality. But more importantly, this builds the groundwork for the in person interview: you can get simple questions out of the way, like what the current projects are, or what types of technology are available. Once you arrive in person, the conversation can continue at depth, and you can do things that are natural in person, like look at data, or be social.
I like to arrive the morning or afternoon before the interview. This gives you a day to take the measure of a city, walk around the university and the downtown, use the public transportation, and see who lives there. One of the most common questions during interviews is, "How do you like living here?" and the best way to answer that is by living there, even for one day out of a hotel. This also gives you a topic of conversation in the lab, and a chance to relax rather than having just stepped off a plane. It may be tempting to have dinner with the lab the night before, but this is too much: it only takes one day to evaluate a lab.*
The night before I like to practice my talk one last time in the privacy of my room, so it's fresh for the morning.
The interview itself should generally run from 10AM-5PM. The late-morning start allows some leeway for jet-lag, and shortens the day so an introverted scientist doesn't get worn out. To some degree, the order of events during the interview is like a baseball lineup, where what you do matters more than the order, but my itinerary would go like this:
10-11: The science talk. This lets the PI (and the lab members) know what the interviewee is doing, so you don't waste time during the one-on-one ("What was my project? Well I'm about to give an hour talk on it...")
11-12: Meet with PI, discussing the standard topics. Hopefully the PI will test the interviewee a bit, and not get lost too much in their data.
12-1: Lunch nearby campus, at a place people actually dine at. It's critical that either lunch or dinner should be without the PI, for it shows he or she trusts their people, and it lets you pump them for info. One interview went disastrously awry when the lab members collectively bitched about their PI.
1-4: Lab tour, meeting with people in the lab, and a break. If you can, go get a coffee (or caramels) to get out of the lab for a bit. After hours of talking and being on, one can get tired, so it's nice to let other people lead the discussions. I also like to get a 30 min break so I can check e-mail and generally veg. out.
4-5: Meet with the PI again to wrap things up.
5: Dinner! Hopefully the PI asked ahead of time if I had any preferences for fare. I'm somewhat of a foodie, so I probably put too much weight on this. Seeing the PI interact with the lab members at dinner is a good measure of their relationship.
And done by seven or eight o'clock, you can decompress in the evening (or even fly out if you want to save time). That's my ideal interview.
*One of my favourite things to do when traveling is discover new restaurants, and the best website I've found for that is Chowhound. It allowed me to discover Serious Pie in Seattle and Fatty Crab in NYC among many others. Message boards like Quarter to Three can help too.