First there was an online test which was quite easy, and a phone interview which wasn't hard. I was invited to the office to interview. There were a total of four interviews, each a bit over half an hour. They were pretty relaxed and friendly. One thing I was curious about was their attitude towards civil liberties in the DC branch, so I mentioned it to the employee I had lunch with. He made it pretty clear that there's a reporting process when you feel that people have had their privacy violated, so it helped me feel that I was applying to an ethical company. That was definitely a big plus for me in the interview process.