I sat down with about 5 of their employees (a principal plus senior staff). After they told me a little about the company, they asked me to walk them through my resume and previous experience. It took about an hour for this portion of the interview, then they gave me a tour of their office and had me meet briefly with other people I'd be working with, should they offer and I accept the job. All in all the people were very friendly and attentive, the office was very nice, clean, spacious, and sunny, even if there were a few cubicle farms scattered throughout.