The interviews started around 8am and didn't end until nearly 6pm. I talked with many different individuals, rotating on approximately an hourly basis. The individual conversations ranged in difficulty. Most of them were fairly relaxed and covered different aspects of my work and research experience. A couple of the interviewers were more difficult and asked situation-based questions. A few of the employees took me out for lunch. At a certain point, I gave an hour-long research talk (focused on my doctoral research). Since Sandia is a National Lab, they expect a fairly technical research talk. I got a lot of great feedback during the talk. Since it was later in the day, I recapped a lot of the talk in my individual interviews. But, I was able to use the presentation in the one-on-one discussions that were scheduled for the late afternoon. The interview process, itself, wasn't too difficult. But, the full day of interviews can be exhausting. Be prepared to talk about your research in many different ways. The people were very nice and easy to talk to. I had a lot of fun getting to know everyone.