Nothing really challenging. They really want to know if you're a cultural fit. It's a bit of an old world mentality. For some reason, in this group, they really liked East Coast / Ivy League educated people and kept exalting that about my qualifications. Frankly, I think that's an overly simplistic approach as there are many other criteria from which to judge a candidate. There was one math question about the easiest way to count the sum of 1 to 99. But nothing overly technical. The interview process and the outcome is somewhat difficult to believe, and if you see signs of this developing with you, don't be caught by surprise. I went on-site twice for 2 full days of interviews, with no planned breaks. It seemed I had spoken with the entire company. Everything indicated that I was going to get an offer, including their own words saying "We are working on the offer package". They ran a background check, checked my references and invited me for a 3rd round, which was a team lunch to "get to meet my co-workers". After being unresponsive for 2 weeks, they finally notified me that I was not selected. It is clear that they were simply holding on to me on the side, until another candidate accepted their offer. A few days is fine, maybe even a week. But after weeks of evasive behavior and even inviting me to have lunch with my 'co-workers' is unbelievable. Everyone there is long-tenured (10 yrs +) so it must be a great place to work, but be careful so you don't get caught in the place I found myself in. It is a huge waste of time. Good luck.