I was first contacted by phone, by one of their recruiters, who then set up an interview with the head of the department I would be interviewing with and then also with their head of HR. That lasted for about 45 minutes, and then they said they would follow up soon if I was asked back for a second interview. I was and interviewed then with the team I would be working with, it was very informal. Each team member took turns to ask me questions based on my resume. Over all despite the fact that I didn't receive an offer the process was positive. However I had to do most of the follow up, even when I was told that they would be following up with me, so if you go into interview keep that in mind.